Imidazoquinoline amine derivatives, pharmaceutical compositions and therapeutic methods thereof

ABSTRACT

The invention provides novel imidazoquinoline amine derivatives, having agonistic activities to Toll-like receptors (TLRs), in particular TLR7 and/or TLR8, pharmaceutical compositions thereof, and methods of treatment, reduction or prevention of certain diseases or conditions mediated by or associated with TLR7 and/or TLR8, e.g., graft rejection, autoimmunity, inflammation allergy, asthma, infection, sepsis, cancer and immunodeficiency.

PRIORITY CLAIMS AND RELATED APPLICATIONS

This application is a continuation of and claims the benefit of priorityto PCT/US2020/015495, filed Jan. 28, 2020, which claims the benefit ofpriority to U.S. Provisional Application No. 62/799,806, filed Feb. 1,2019, the content of each of which is incorporated herein by referencein its entirety.

TECHNICAL FIELD OF THE INVENTION

The invention generally relates to novel compounds and therapeutic usesthereof. More particularly, the invention provides novelimidazoquinoline amine derivatives, having agonistic activities towardsToll-like receptors (TLRs), in particular TLR7 and/or TLR8,pharmaceutical compositions thereof, and methods of treatment, reductionor prevention of certain diseases or conditions mediated by orassociated with TLR7 and/or TLR8, e.g., graft rejection, autoimmunity,inflammation allergy, asthma, infection, sepsis, cancer andimmunodeficiency.

BACKGROUND OF THE INVENTION

Innate and adaptive immunities are the two arms of the vertebratedefense system against pathogen infections. (Isaza-Correa et al. 2004Nat Immunol 5:987-995; Kawai et al. 2006 Nat Immunol 7:131-137; Kimbrellet al. 2001 Nat Rev Genet 2:256-267.) TLRs are one of the most importantregulators of both innate and adaptive immune responses because they areable to detect pathogen associated molecular patterns and dangerassociated molecular patterns (DAMPs). (Basith et al. 2012 Arch PharmRes 35:1297-1316; Vijay 2018 Int Immunopharmacol 59:391-412.) TLRs arehighly conserved in both vertebrates and invertebrates. TLRs 1, 2, 4, 5,6 and 10 are located on the cell surface, while TLRs 3, 7, 8, 9, 11, 12and 13 are localized to endosomal/lysosomal vesicles. The ten TLRs inhumans (TLR1-10) are expressed by B cells, dendritic cells (DCs), Tcells, monocytes and macrophages. (Kawai et al. 2011 Immunity34:637-650; Lee et al. 2012 Nat Rev Immunol 12:168-179.) The nativeligands of TLR1-9 were identified while TLR10 ligand is still unknown.The capacity of TLRs to recognize specific components expressed bybacteria, fungi, protozoa and viruses is a crucial element of the innateresponse (Iwasaki et al. 2015 Nat Immunol; 16:343-353). These microbialcomponents can be categorized into three main classes: lipids andlipopeptides (TLR2/1; TLR2/6; TLR2 and TLR4 agonists); flagellin (TLR5agonists); and nucleic acids (TLR3, 7, 8 and 9 agonists).

Stimulation of TLRs to activate the innate immune system has been atherapeutic strategy for some years. TLRs 3, 4, 7, 8 and 9 are allvalidated targets for cancer and a number of companies are developingagonists and vaccine adjuvants. (Holldack 2013 Drug Discov Today19:379-382.) TLR7 in particular has established proof-of-concept as atarget in the topical treatment of bladder and skin cancers. However,the development of systemic treatments targeting TLR7 for most othercancers has proved difficult owing to cardiotoxicity ormyelosuppression. Recent animal data have demonstrated that a new classof modified TLR7 agonists can be administered systemically with a goodtoxicology profile, opening up this target in therapeutic interventionsfor systemic cancers.

TLR7 and 8 are located on endosomal membranes of antigen-presentingcells (APCs), including monocytes and macrophages. TLR7 is highlyexpressed on plasmacytoid DCs (pDCs), while TLR8 is mainly expressed onmyeloid DCs (mDCs) and monocytes. The activation of TLR8 results in theproduction of various cytokines such as IL-6, IL-12, TNF-α and IFN-β,and increases the expression of costimulatory molecules, for example,CD40, CD80, CD83 and CD86, MHC molecules and chemokine receptors.(Hussein et al. 2014 Expert Opin Ther Pat 24:453-470.) Moreover,stimulation of TLR8 leads to the production of IFN-α and IFN-β. As TLR7and 8 can recognize viral ssRNA, the investigation of new TLR7 and 8agonists may lead to the development of new antiviral vaccines.

A large series of purine derivatives including phospholipid conjugateswas synthesized for use as TLR7 agonists. These compounds were used asvaccine adjuvants and to prevent, inhibit or treat a variety ofdisorders like inflammation, cancer and microbial infections (Hayashi etal. 2011 Melanoma Res 21:66-75). VTX-2337 is a benzo[b]azepinederivative that can induce the potent activation and type 1 polarizationof human myeloid DCs via stimulation of TLR8. Imiquimod, a syntheticimidazoquinoline, is the first TLR7 agonist approved by the FDA in atopical 5% formulation for the treatment of external genital warts,superficial basal cell carcinoma and actinic keratosis. (Hemmi et al.2002 Nat Immunol 3:196-200; Wang et al. 2008 Oncogene 27:181-189.) Asmall molecule derivative of imidazoquinoline, 852A, is another TLR7agonist. Activity, safety and immunostimulating ability of prolongeddosing of 852A were evaluated in a Phase II clinical trial for thetreatment of patients with recurrent hematologic malignancies. (Weigelet al. 2012 Am J Hematol 87:953-956). This study, however, wasterminated because the drug was no longer available from the sponsor(NCT00276159.)

The therapeutics and methods currently available for the management ofdiseases or disorders associated with TLRs 7 and 8 are inadequate. Thereremains an urgent and ongoing need for novel and improved therapeuticsto effectively treat such diseases and conditions.

SUMMARY OF THE INVENTION

The invention is based in part on the unexpected discovery of novelimidazoquinoline amine derivatives, which are agonists of TLRs, inparticular TLR7 and/or TLR8, pharmaceutical compositions thereof, andmethods of treatment, reduction or prevention of certain diseases orconditions mediated by or associated with TLR7 and/or TLR8, e.g., graftrejection, autoimmunity, inflammation allergy, asthma, infection,sepsis, cancer and immunodeficiency, and related diseases andconditions.

In one aspect, the invention generally relates to a compound having thestructural formula (I):

wherein,

R¹ is a C₁-C₈ (e.g., C₁-C₄, C₄-C₆, C₆-C₈) alkyl group;

R² is (CH₂)_(m), wherein m is an integer selected from 1 to 8 (e.g., 1,2, 3, 4, 5, 6, 7, 8);

L is a linking moiety; and

R³ is a C₁-C₃₂ (e.g., C₁-C₁₆, C₁₆-C₃₂, C₁₆-C₂₄) alkyl group;

or a pharmaceutically acceptable form or an isotope derivative thereof.

In another aspect, the invention generally relates to a pharmaceuticalcomposition comprising a compound disclosed herein.

In yet another aspect, the invention generally relates to apharmaceutical composition comprising an amount of a compound having thestructural formula (I):

wherein,

R¹ is a C₁-C₈ (e.g., C₁-C₄, C₄-C₆, C₆-C₈) alkyl group;

R² is (CH₂)_(m), wherein m is an integer selected from 1 to 8 (e.g., 1,2, 3, 4, 5, 6, 7, 8);

L is a linking moiety; and

R³ is a C₁-C₃₂ (e.g., C₁-C₁₆, C₁₆-C₃₂, C₁₆-C₂₄) alkyl group;

or a pharmaceutically acceptable form or an isotope derivative thereof,effective to treat, prevent, or reduce one or more diseases ordisorders, in a mammal, including a human, and a pharmaceuticallyacceptable excipient, carrier, or diluent.

In yet another aspect, the invention generally relates to a unit dosageform comprising a compound disclosed herein.

In yet another aspect, the invention generally relates to a unit dosageform comprising a pharmaceutical composition disclosed herein.

In yet another aspect, the invention generally relates to a method fortreating, reducing, or preventing a disease or disorder, comprisingadministering to a subject in need thereof a pharmaceutical compositioncomprising a compound having the structural formula (I):

wherein,

R¹ is a C₁-C₈ (e.g., C₁-C₄, C₄-C₆, C₆-C₈) alkyl group;

R² is (CH₂)_(m), wherein m is an integer selected from 1 to 8 (e.g., 1,2, 3, 4, 5, 6, 7, 8);

L is a linking moiety; and

R³ is a C₁-C₃₂ (e.g., C₁-C₁₆, C₁₆-C₃₂, C₁₆-C₂₄) alkyl group;

or a pharmaceutically acceptable form or an isotope derivative thereof,effective to treat, reduce or prevent or one or more of autoimmunediseases, graft rejection, allergies, immunodeficiency, infection,sepsis, cancer, or a related disease or disorder thereof, in a mammal,including a human, and a pharmaceutically acceptable excipient, carrier,or diluent.

In yet another aspect, the invention generally relates to a method formodulating immune response, comprising administering to a subject inneed thereof a pharmaceutical composition comprising a compounddisclosed herein.

In yet another aspect, the invention generally relates to a method formodulating TLR7- and/or TLR8-mediated signaling, comprisingadministering to a subject in need thereof a pharmaceutical compositioncomprising a compound disclosed herein.

In yet another aspect, the invention generally relates to a method forof treating, reducing, or preventing a condition or disorder treatableby modulation of TLR7- and/or TLR8-mediated cellular activities,comprising administering to a subject in need thereof a pharmaceuticalcomposition comprising a compound disclosed herein.

In yet another aspect, the invention generally relates to a method fortreating, reducing, or preventing a disease or disorder, comprisingadministering to a subject in need thereof a pharmaceutical compositioncomprising a compound disclosed herein, wherein the disease or disorderis autoimmune diseases, graft rejection, allergies, immunodeficiency,infection, sepsis, cancer, or a related disease or disorder.

In yet another aspect, the invention generally relates to use of acompound disclosed herein for treating, reducing or preventing a diseaseor disorder.

In yet another aspect, the invention generally relates to use of acompound disclosed herein and a pharmaceutically acceptable excipient,carrier, or diluent, in preparation of a medicament for treating,reducing or preventing a disease or disorder.

Definitions

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this invention belongs. General principles of organicchemistry, as well as specific functional moieties and reactivity, aredescribed in “Organic Chemistry”, Thomas Sorrell, University ScienceBooks, Sausalito: 1999, and “March's Advanced Organic Chemistry”, 5^(th)Ed.: Smith, M. B. and March, J., John Wiley & Sons, New York: 2001, theentire contents of which are hereby incorporated by reference.

Certain compounds of the present invention may exist in particulargeometric or stereoisomeric forms. The present invention contemplatesall such compounds, including cis- and trans-isomers, R- andS-enantiomers, diastereomers, (D)-isomers, (L)-isomers, the racemicmixtures thereof, and other mixtures thereof, as falling within thescope of the invention. Additional asymmetric carbon atoms may bepresent in a substituent such as an alkyl group. All such isomers, aswell as mixtures thereof, are intended to be included in this invention.

Isomeric mixtures containing any of a variety of isomer ratios may beutilized in accordance with the present invention. For example, whereonly two isomers are combined, mixtures containing 50:50, 60:40, 70:30,80:20, 90:10, 95:5, 96:4, 97:3, 98:2, 99:1, or 100:0 isomer ratios arecontemplated by the present invention. Those of ordinary skill in theart will readily appreciate that analogous ratios are contemplated formore complex isomer mixtures.

If, for instance, a particular enantiomer of a compound of the presentinvention is desired, it may be prepared by asymmetric synthesis, or byderivation with a chiral auxiliary, where the resulting diastereomericmixture is separated and the auxiliary group cleaved to provide the puredesired enantiomers. Alternatively, where the molecule contains a basicfunctional group, such as amino, or an acidic functional group, such ascarboxyl, diastereomeric salts are formed with an appropriateoptically-active acid or base, followed by resolution of thediastereomers thus formed by fractional crystallization orchromatographic methods well known in the art, and subsequent recoveryof the pure enantiomers.

Solvates and polymorphs of the compounds of the invention are alsocontemplated herein. Solvates of the compounds of the present inventioninclude, for example, hydrates.

Definitions of specific functional groups and chemical terms aredescribed in more detail below. When a range of values is listed, it isintended to encompass each value and sub-range within the range. Forexample, “C₁₋₆ alkyl” is intended to encompass, C₁, C₂, C₃, C₄, C₅, C₆,C₁₋₆, C₁₋₅, C₁₋₄, C₁₋₃, C₁₋₂, C₂₋₆, C₂₋₅, C₂₋₄, C₂₋₃, C₃₋₆, C₃₋₅, C₃₋₄,C₄₋₆, C₄₋₅, and C₅₋₆ alkyl.

As used herein, the term “alkyl” refers to a straight, branched orcyclic hydrocarbon radical consisting solely of carbon and hydrogenatoms, containing no unsaturation, having from one to ten carbon atoms(e.g., C₁₋₁₀ alkyl). Whenever it appears herein, a numerical range suchas “1 to 10” refers to each integer in the given range; e.g., “1 to 10carbon atoms” means that the alkyl group can consist of 1 carbon atom, 2carbon atoms, 3 carbon atoms, etc., up to and including 10 carbon atoms,although the present definition also covers the occurrence of the term“alkyl” where no numerical range is designated. In some embodiments,“alkyl” can be a C₁₋₆ alkyl group. In some embodiments, alkyl groupshave 1 to 10, 1 to 8, 1 to 6, or 1 to 3 carbon atoms.

Representative saturated straight chain alkyls include, but are notlimited to, -methyl, -ethyl, -n-propyl, -n-butyl, -n-pentyl, and-n-hexyl; while saturated branched alkyls include, but are not limitedto, -isopropyl, -sec-butyl, -isobutyl, -tert-butyl, -isopentyl,2-methylbutyl, 3-methylbutyl, 2-methylpentyl, 3-methylpentyl,4-methylpentyl, 2-methylhexyl, 3-methylhexyl, 4-methylhexyl,5-methylhexyl, 2,3-dimethylbutyl, and the like. The alkyl is attached tothe parent molecule by a single bond.

Unless stated otherwise in the specification, an alkyl group isoptionally substituted by one or more of substituents whichindependently include: acyl, alkyl, alkenyl, alkynyl, alkoxy, alkylaryl,cycloalkyl, aralkyl, aryl, aryloxy, amino, amido, amidino, imino, azide,carbonate, carbamate, carbonyl, heteroalkyl, heteroaryl,heteroarylalkyl, heterocycloalkyl, hydroxy, cyano, halo (F, Cl, Br, I),haloalkoxy, haloalkyl, ester, ether, mercapto, thio, alkylthio,arylthio, thiocarbonyl, nitro, oxo, phosphate, phosphonate, phosphinate,silyl, sulfinyl, sulfonyl, sulfonamidyl, sulfoxyl, sulfonate, urea,—Si(R^(a))₃, —OR^(a), —SR^(a), —OC(O)—R^(a), —N(R^(a))₂, —C(O)R_(a),—C(O)OR^(a), —OC(O)N(R^(a))₂, —C(O)N(R^(a))₂, —N(R^(a))C(O)OR^(a),—N(R^(a))C(O)R^(a), —N(R^(a))C(O)N(R^(a))₂, —N(R^(a))C(NR^(a))N(R^(a))₂,—N(R^(a))S(O)_(t)N(R^(a))₂ (where t is 1 or 2), —P(═O)(R^(a))(R^(a)), or—O—P(═O)(OR^(a))₂ where each R^(a) is independently hydrogen, alkyl,haloalkyl, carbocyclyl, carbocyclylalkyl, aryl, aralkyl,heterocycloalkyl, heterocycloalkylalkyl, heteroaryl or heteroarylalkyl,and each of these moieties can be optionally substituted as definedherein. In a non-limiting embodiment, a substituted alkyl can beselected from fluoromethyl, difluoromethyl, trifluoromethyl,2-fluoroethyl, 3-fluoropropyl, hydroxymethyl, 2-hydroxyethyl,3-hydroxypropyl, benzyl, and phenethyl.

As used herein, the terms “aliphatic” or “aliphatic group” means astraight-chain (i.e., unbranched) or branched, substituted orunsubstituted hydrocarbon chain that is completely saturated or thatcontains one or more units of unsaturation, or a monocyclic hydrocarbonor bicyclic hydrocarbon that is completely saturated or that containsone or more units of unsaturation, but which is not aromatic, that has asingle point of attachment to the rest of the molecule. Unless otherwisespecified, aliphatic groups contain 1-6 aliphatic carbon atoms. In someembodiments, aliphatic groups contain 1-5 aliphatic carbon atoms. Inother embodiments, aliphatic groups contain 1-4 aliphatic carbon atoms.In still other embodiments, aliphatic groups contain 1-3 aliphaticcarbon atoms, and in yet other embodiments, aliphatic groups contain 1-2aliphatic carbon atoms. In some embodiments, “cycloaliphatic” refers toa monocyclic C₃-C₆ hydrocarbon that is completely saturated or thatcontains one or more units of unsaturation, but which is not aromatic,that has a single point of attachment to the rest of the molecule.Exemplary aliphatic groups are linear or branched, substituted orunsubstituted C₁-C₈ alkyl, C₂-C₈ alkenyl, C₂-C₈ alkynyl groups andhybrids thereof such as (cycloalkyl)alkyl, (cycloalkenyl)alkyl or(cycloalkyl)alkenyl.

As used herein, the term “heteroatom” means one or more of oxygen,sulfur, nitrogen, or phosphorus (including, any oxidized form ofnitrogen, sulfur, or phosphorus; the quaternized form of any basicnitrogen or; a substitutable nitrogen of a heterocyclic ring, forexample N (as in 3,4-dihydro-2H-pyrrolyl), NH (as in pyrrolidinyl) orNR⁺ (as in N-substituted pyrrolidinyl)).

The term “unsaturated”, as used herein, means that a moiety has one ormore units of unsaturation.

As used herein, the term “alkylene” refers to a bivalent alkyl group. An“alkylene chain” is a polymethylene group, i.e., —(CH₂)_(n)—, wherein nis a positive integer, preferably from 1 to 6, from 1 to 4, from 1 to 3,from 1 to 2, or from 2 to 3. A substituted alkylene chain is apolymethylene group in which one or more methylene hydrogen atoms arereplaced with a substituent. Suitable substituents include thosedescribed below for a substituted aliphatic group.

As used herein, the term “halogen” refers to fluorine (F), chlorine(Cl), bromine (Br), or iodine (I). As used herein, the term “halide” or“halo”, means fluoro, chloro, bromo or iodo. The terms “haloalkyl,”“haloalkenyl,” “haloalkynyl” and “haloalkoxy” include alkyl, alkenyl,alkynyl and alkoxy structures that are substituted with one or more halogroups or with combinations thereof. For example, the terms“fluoroalkyl” and “fluoroalkoxy” include haloalkyl and haloalkoxygroups, respectively, in which the halo is fluorine, such as, but notlimited to, trifluoromethyl, difluoromethyl, 2,2,2-trifluoroethyl,1-fluoromethyl-2-fluoroethyl, and the like. Each of the alkyl, alkenyl,alkynyl and alkoxy groups are as defined herein and can be optionallyfurther substituted as defined herein.

As used herein, the term “alkoxy” refers to the group —O-alkyl,including from 1 to 10 carbon atoms (C₁₋₁₀) of a straight, branched,saturated cyclic configuration and combinations thereof, attached to theparent molecular structure through an oxygen. Examples include methoxy,ethoxy, propoxy, isopropoxy, butoxy, t-butoxy, pentoxy, cyclopropyloxy,cyclohexyloxy and the like. “Lower alkoxy” refers to alkoxy groupscontaining one to six carbons. In some embodiments, C₁₋₃ alkoxy is analkoxy group that encompasses both straight and branched chain alkyls offrom 1 to 3 carbon atoms. Unless stated otherwise in the specification,an alkoxy group can be optionally substituted by one or moresubstituents which independently include: acyl, alkyl, alkenyl, alkynyl,alkoxy, alkylaryl, cycloalkyl, aralkyl, aryl, aryloxy, amino, amido,amidino, imino, azide, carbonate, carbamate, carbonyl, heteroalkyl,heteroaryl, heteroarylalkyl, heterocycloalkyl, hydroxy, cyano, halo,haloalkoxy, haloalkyl, ester, ether, mercapto, thio, alkylthio,arylthio, thiocarbonyl, nitro, oxo, phosphate, phosphonate, phosphinate,silyl, sulfinyl, sulfonyl, sulfonamidyl, sulfoxyl, sulfonate, urea,—Si(R^(a))₃, —OR^(a), —SR^(a), —OC(O)—R^(a), —N(R^(a))₂, —C(O)R_(a),—C(O)OR^(a), —OC(O)N(R^(a))₂, —C(O)N(R^(a))₂, —N(R^(a))C(O)OR^(a),—N(R^(a))C(O)R^(a), —N(R^(a))C(O)N(R^(a))₂, —N(R^(a))C(NR^(a))N(R^(a))₂,—N(R^(a))S(O)_(t)N(R^(a))₂ (where t is 1 or 2), —P(═O)(R^(a))(R^(a)), or—O—P(═O)(OR^(a))₂ where each R^(a) is independently hydrogen, alkyl,haloalkyl, carbocyclyl, carbocyclylalkyl, aryl, aralkyl,heterocycloalkyl, heterocycloalkylalkyl, heteroaryl or heteroarylalkyl,and each of these moieties can be optionally substituted as definedherein.

As used herein, the terms “aromatic” or “aryl” refer to a radical with 6to 14 ring atoms (e.g., C₆₋₁₄ aromatic or C₆₋₁₄ aryl) that has at leastone ring having a conjugated pi electron system which is carbocyclic(e.g., phenyl, fluorenyl, and naphthyl). In some embodiments, the arylis a C₆₋₁₀ aryl group. For example, bivalent radicals formed fromsubstituted benzene derivatives and having the free valences at ringatoms are named as substituted phenylene radicals. In other embodiments,bivalent radicals derived from univalent polycyclic hydrocarbon radicalswhose names end in “-yl” by removal of one hydrogen atom from the carbonatom with the free valence are named by adding “-idene” to the name ofthe corresponding univalent radical, e.g., a naphthyl group with twopoints of attachment is termed naphthylidene. Whenever it appearsherein, a numerical range such as “6 to 14 aryl” refers to each integerin the given range; e.g., “6 to 14 ring atoms” means that the aryl groupcan consist of 6 ring atoms, 7 ring atoms, etc., up to and including 14ring atoms. The term includes monocyclic or fused-ring polycyclic (i.e.,rings which share adjacent pairs of ring atoms) groups. Polycyclic arylgroups include bicycles, tricycles, tetracycles, and the like. In amulti-ring group, only one ring is required to be aromatic, so groupssuch as indanyl are encompassed by the aryl definition. Non-limitingexamples of aryl groups include phenyl, phenalenyl, naphthalenyl,tetrahydronaphthyl, phenanthrenyl, anthracenyl, fluorenyl, indolyl,indanyl, and the like. Unless stated otherwise in the specification, anaryl moiety can be optionally substituted by one or more substituentswhich independently include: acyl, alkyl, alkenyl, alkynyl, alkoxy,alkylaryl, cycloalkyl, aralkyl, aryl, aryloxy, amino, amido, amidino,imino, azide, carbonate, carbamate, carbonyl, heteroalkyl, heteroaryl,heteroarylalkyl, heterocycloalkyl, hydroxy, cyano, halo, haloalkoxy,haloalkyl, ester, ether, mercapto, thio, alkylthio, arylthio,thiocarbonyl, nitro, oxo, phosphate, phosphonate, phosphinate, silyl,sulfinyl, sulfonyl, sulfonamidyl, sulfoxyl, sulfonate, urea,—Si(R^(a))₃, —OR^(a), —SR^(a), —OC(O)—R^(a), —N(R^(a))₂, —C(O)R_(a),—C(O)OR^(a), —OC(O)N(R^(a))₂, —C(O)N(R^(a))₂, —N(R^(a))C(O)OR^(a),—N(R^(a))C(O)R^(a), —N(R^(a))C(O)N(R^(a))₂, —N(R^(a))C(NR^(a))N(R^(a))₂,—N(R^(a))S(O)_(t)N(R^(a))₂ (where t is 1 or 2), —P(═O)(R^(a))(R^(a)), or—O—P(═O)(OR^(a))₂ where each R^(a) is independently hydrogen, alkyl,haloalkyl, carbocyclyl, carbocyclylalkyl, aryl, aralkyl,heterocycloalkyl, heterocycloalkylalkyl, heteroaryl or heteroarylalkyl,and each of these moieties can be optionally substituted as definedherein.

As used herein, the terms “cycloalkyl” and “carbocyclyl” each refers toa monocyclic or polycyclic radical that contains only carbon andhydrogen, and can be saturated or partially unsaturated. Partiallyunsaturated cycloalkyl groups can be termed “cycloalkenyl” if thecarbocycle contains at least one double bond, or “cycloalkynyl” if thecarbocycle contains at least one triple bond. Cycloalkyl groups includegroups having from 3 to 13 ring atoms (i.e., C₃₋₁₃ cycloalkyl). Wheneverit appears herein, a numerical range such as “3 to 10” refers to eachinteger in the given range; e.g., “3 to 13 carbon atoms” means that thecycloalkyl group can consist of 3 carbon atoms, 4 carbon atoms, 5 carbonatoms, etc., up to and including 13 carbon atoms. The term “cycloalkyl”also includes bridged and spiro-fused cyclic structures containing noheteroatoms. The term also includes monocyclic or fused-ring polycyclic(i.e., rings which share adjacent pairs of ring atoms) groups.Polycyclic aryl groups include bicycles, tricycles, tetracycles, and thelike. In some embodiments, “cycloalkyl” can be a C₃₋₈ cycloalkylradical. In some embodiments, “cycloalkyl” can be a C₃₋₅ cycloalkylradical. Illustrative examples of cycloalkyl groups include, but are notlimited to the following moieties: C₃₋₆ carbocyclyl groups include,without limitation, cyclopropyl (C₃), cyclobutyl (C₄), cyclopentyl (C₅),cyclopentenyl (C₅), cyclohexyl (C₆), cyclohexenyl (C₆), cyclohexadienyl(C₆) and the like. Examples of C₃₋₇ carbocyclyl groups include norbornyl(C₇). Examples of C₃₋₈ carbocyclyl groups include the aforementionedC₃₋₇ carbocyclyl groups as well as cycloheptyl (C₇), cycloheptadienyl(C₇), cycloheptatrienyl (C₇), cyclooctyl (C₈), bicyclo[2.2.1]heptanyl,bicyclo[2.2.2]octanyl, and the like. Examples of C₃₋₁₃ carbocyclylgroups include the aforementioned C₃₋₈ carbocyclyl groups as well asoctahydro-1H indenyl, decahydronaphthalenyl, spiro[4.5]decanyl and thelike. Unless stated otherwise in the specification, a cycloalkyl groupcan be optionally substituted by one or more substituents whichindependently include: acyl, alkyl, alkenyl, alkynyl, alkoxy, alkylaryl,cycloalkyl, aralkyl, aryl, aryloxy, amino, amido, amidino, imino, azide,carbonate, carbamate, carbonyl, heteroalkyl, heteroaryl,heteroarylalkyl, heterocycloalkyl, hydroxy, cyano, halo, haloalkoxy,haloalkyl, ester, ether, mercapto, thio, alkylthio, arylthio,thiocarbonyl, nitro, oxo, phosphate, phosphonate, phosphinate, silyl,sulfinyl, sulfonyl, sulfonamidyl, sulfoxyl, sulfonate, urea,—Si(R^(a))₃, —OR^(a), —SR^(a), —OC(O)—R^(a), —N(R^(a))₂, —C(O)R_(a),—C(O)OR^(a), —OC(O)N(R^(a))₂, —C(O)N(R^(a))₂, —N(R^(a))C(O)OR^(a),—N(R^(a))C(O)R^(a), —N(R^(a))C(O)N(R^(a))₂, —N(R^(a))C(NR^(a))N(R^(a))₂,—N(R^(a))S(O)_(t)N(R^(a))₂ (where t is 1 or 2), —P(═O)(R^(a))(R^(a)), or—O—P(═O)(OR^(a))₂ where each R^(a) is independently hydrogen, alkyl,haloalkyl, carbocyclyl, carbocyclylalkyl, aryl, aralkyl,heterocycloalkyl, heterocycloalkylalkyl, heteroaryl or heteroarylalkyl,and each of these moieties can be optionally substituted as definedherein. The terms “cycloalkenyl” and “cycloalkynyl” mirror the abovedescription of “cycloalkyl” wherein the prefix “alk” is replaced with“alken” or “alkyn” respectively, and the parent “alkenyl” or “alkynyl”terms are as described herein. For example, a cycloalkenyl group canhave 3 to 13 ring atoms, such as 5 to 8 ring atoms. In some embodiments,a cycloalkynyl group can have 5 to 13 ring atoms.

As used herein, the term “heteroalkyl” refers to an alkyl radical, whichhave one or more skeletal chain atoms being an atom other than carbon,e.g., oxygen, nitrogen, sulfur, phosphorus or combinations thereof. Anumerical range can be given, e.g., C₁₋₄ heteroalkyl, which refers tothe chain length in total, which in this example is 4 atoms long. Forexample, a —CH₂OCH₂CH₃ radical is referred to as a “C₄” heteroalkyl,which includes the heteroatom center in the atom chain lengthdescription. Connection to the parent molecular structure can be througheither a heteroatom or a carbon in the heteroalkyl chain. For example,an N-containing heteroalkyl moiety refers to a group in which at leastone of the skeletal atoms is a nitrogen atom. One or more heteroatom(s)in the heteroalkyl radical can be optionally oxidized. One or morenitrogen atoms, if present, can also be optionally quaternized. Forexample, heteroalkyl also includes skeletal chains substituted with oneor more nitrogen oxide (—O—) substituents. Exemplary heteroalkyl groupsinclude, without limitation, ethers such as methoxyethanyl(—CH₂CH₂OCH₃), ethoxymethanyl (—CH₂OCH₂CH₃), (methoxymethoxy)ethanyl(—CH₂CH₂OCH₂OCH₃), (methoxymethoxy) methanyl (—CH₂OCH₂OCH₃) and(methoxyethoxy)methanyl (—CH₂OCH₂CH₂OCH₃) and the like; amines such as(—CH₂CH₂NHCH₃, —CH₂CH₂N(CH₃)₂, —CH₂NHCH₂CH₃, —CH₂N(CH₂CH₃)(CH₃)) and thelike.

As used herein, the term “heteroaryl” or “heteroaromatic” refers to arefers to a radical of a 5-18 membered monocyclic or polycyclic (e.g.,bicyclic, tricyclic, tetracyclic and the like) aromatic ring system(e.g., having 6, 10 or 14π electrons shared in a cyclic array) havingring carbon atoms and 1-6 ring heteroatoms provided in the aromatic ringsystem, wherein each heteroatom is independently selected from nitrogen,oxygen, phosphorous and sulfur. Heteroaryl polycyclic ring systems caninclude one or more heteroatoms in one or both rings. Whenever itappears herein, a numerical range such as “5 to 18” refers to eachinteger in the given range; e.g., “5 to 18 ring atoms” means that theheteroaryl group can consist of 5 ring atoms, 6 ring atoms, etc., up toand including 18 ring atoms. In some instances, a heteroaryl can have 5to 14 ring atoms. In some embodiments, the heteroaryl has, for example,bivalent radicals derived from univalent heteroaryl radicals whose namesend in “-yl” by removal of one hydrogen atom from the atom with the freevalence are named by adding “-ene” to the name of the correspondingunivalent radical, e.g., a pyridyl group with two points of attachmentis a pyridylene.

For example, an N-containing “heteroaromatic” or “heteroaryl” moietyrefers to an aromatic group in which at least one of the skeletal atomsof the ring is a nitrogen atom. One or more heteroatom(s) in theheteroaryl radical can be optionally oxidized. One or more nitrogenatoms, if present, can also be optionally quaternized. Heteroaryl alsoincludes ring systems substituted with one or more nitrogen oxide (—O—)substituents, such as pyridinyl N-oxides. The heteroaryl is attached tothe parent molecular structure through any atom of the ring(s).

“Heteroaryl” also includes ring systems wherein the heteroaryl ring, asdefined above, is fused with one or more aryl groups wherein the pointof attachment to the parent molecular structure is either on the aryl oron the heteroaryl ring, or wherein the heteroaryl ring, as definedabove, is fused with one or more cycloalkyl or heterocycyl groupswherein the point of attachment to the parent molecular structure is onthe heteroaryl ring. For polycyclic heteroaryl groups wherein one ringdoes not contain a heteroatom (e.g., indolyl, quinolinyl, carbazolyl andthe like), the point of attachment to the parent molecular structure canbe on either ring, i.e., either the ring bearing a heteroatom (e.g.,2-indolyl) or the ring that does not contain a heteroatom (e.g.,5-indolyl). In some embodiments, a heteroaryl group is a 5-10 memberedaromatic ring system having ring carbon atoms and 1-4 ring heteroatomsprovided in the aromatic ring system, wherein each heteroatom isindependently selected from nitrogen, oxygen, phosphorous, and sulfur(“5-10 membered heteroaryl”). In some embodiments, a heteroaryl group isa 5-8 membered aromatic ring system having ring carbon atoms and 1-4ring heteroatoms provided in the aromatic ring system, wherein eachheteroatom is independently selected from nitrogen, oxygen, phosphorous,and sulfur (“5-8 membered heteroaryl”). In some embodiments, aheteroaryl group is a 5-6 membered aromatic ring system having ringcarbon atoms and 1-4 ring heteroatoms provided in the aromatic ringsystem, wherein each heteroatom is independently selected from nitrogen,oxygen, phosphorous, and sulfur (“5-6 membered heteroaryl”). In someembodiments, the 5-6 membered heteroaryl has 1-3 ring heteroatomsselected from nitrogen, oxygen, phosphorous, and sulfur. In someembodiments, the 5-6 membered heteroaryl has 1-2 ring heteroatomsselected from nitrogen, oxygen, phosphorous, and sulfur. In someembodiments, the 5-6 membered heteroaryl has 1 ring heteroatom selectedfrom nitrogen, oxygen, phosphorous, and sulfur.

Examples of heteroaryls include, but are not limited to, azepinyl,acridinyl, benzimidazolyl, benzindolyl, 1,3-benzodioxolyl, benzofuranyl,benzooxazolyl, benzo[d]thiazolyl, benzothiadiazolyl,benzo[b][1,4]dioxepinyl, benzo[b][1,4] oxazinyl, 1,4-benzodioxanyl,benzonaphthofuranyl, benzoxazolyl, benzodioxolyl, benzodioxinyl,benzoxazolyl, benzopyranyl, benzopyranonyl, benzofuranyl,benzopyranonyl, benzofurazanyl, benzothiazolyl, benzothienyl(benzothiophenyl), benzothieno[3,2-d]pyrimidinyl, benzotriazolyl,benzo[4,6]imidazo[1,2-a]pyridinyl, carbazolyl, cinnolinyl,cyclopenta[d]pyrimidinyl, 6,7-dihydro-5H-cyclopenta[4,5]thieno[2,3-d]pyrimidinyl, 5,6-dihydrobenzo[h]quinazolinyl,5,6-dihydrobenzo[h]cinnolinyl, 6,7-dihydro-5Hbenzo[6,7]cyclohepta[1,2-c]pyridazinyl, dibenzofuranyl,dibenzothiophenyl, furanyl, furazanyl, furanonyl, furo [3,2-c]pyridinyl,5,6,7,8,9,10-hexahydrocycloocta[d] pyrimidinyl,5,6,7,8,9,10-hexahydrocycloocta[d]pyridazinyl,5,6,7,8,9,10-hexahydrocycloocta[d]pyridinyl, isothiazolyl, imidazolyl,indazolyl, indolyl, indazolyl, isoindolyl, indolinyl, isoindolinyl,isoquinolyl, indolizinyl, isoxazolyl,5,8-methano-5,6,7,8-tetrahydroquinazolinyl, naphthyridinyl,1,6-naphthyridinonyl, oxadiazolyl, 2-oxoazepinyl, oxazolyl, oxiranyl,5,6,6a,7,8,9,10,10a-octahydrobenzo[h]quinazolinyl, 1-phenyl-1H-pyrrolyl,phenazinyl, phenothiazinyl, phenoxazinyl, phthalazinyl, pteridinyl,purinyl, pyranyl, pyrrolyl, pyrazolyl, pyrazolo[3,4-d]pyrimidinyl,pyridinyl, pyrido[3,2-d]pyrimidinyl, pyrido[3,4-d]pyrimidinyl,pyrazinyl, pyrimidinyl, pyridazinyl, pyrrolyl, quinazolinyl,quinoxalinyl, quinolinyl, isoquinolinyl, tetrahydroquinolinyl,5,6,7,8-tetrahydroquinazolinyl, 5,6,7,8-tetrahydrobenzo [4,5] thieno[2,3-d]pyrimdinyl, 6,7,8,9-tetrahydro-5H-cyclohepta[4,5]thieno[2,3-d]pyrimidinyl, 5,6,7,8-tetrahydropyrido[4,5-c]pyridazinyl,thiazolyl, thiadiazolyl, thiapyranyl, triazolyl, tetrazolyl, triazinyl,thieno[2,3-d]pyrimidinyl, thieno[3,2-d]pyrimidinyl, thieno[2,3-c]pridinyl, and thiophenyl (i.e., thienyl). Unless stated otherwisein the specification, a heteroaryl moiety can be optionally substitutedby one or more substituents which independently include: acyl, alkyl,alkenyl, alkynyl, alkoxy, alkylaryl, cycloalkyl, aralkyl, aryl, aryloxy,amino, amido, amidino, imino, azide, carbonate, carbamate, carbonyl,heteroalkyl, heteroaryl, heteroarylalkyl, heterocycloalkyl, hydroxy,cyano, halo, haloalkoxy, haloalkyl, ester, ether, mercapto, thio,alkylthio, arylthio, thiocarbonyl, nitro, oxo, phosphate, phosphonate,phosphinate, silyl, sulfinyl, sulfonyl, sulfonamidyl, sulfoxyl,sulfonate, urea, —Si(R^(a))₃, —OR^(a), —SR^(a), —OC(O)—R^(a),—N(R^(a))₂, —C(O)R_(a), —C(O)OR^(a), —OC(O)N(R^(a))₂, —C(O)N(R^(a))₂,—N(R^(a))C(O)OR^(a), —N(R^(a))C(O)R^(a), —N(R^(a))C(O)N(R^(a))₂,—N(R^(a))C(NR^(a))N(R^(a))₂, —N(R^(a))S(O)_(t)N(R^(a))₂ (where t is 1 or2), —P(═O)(R^(a))(R^(a)), or —O—P(═O)(OR^(a))₂ where each R^(a) isindependently hydrogen, alkyl, haloalkyl, carbocyclyl, carbocyclylalkyl,aryl, aralkyl, heterocycloalkyl, heterocycloalkylalkyl, heteroaryl orheteroarylalkyl, and each of these moieties can be optionallysubstituted as defined herein.

As used herein, the terms “TLR7 and/or TLR8 ligand,” “ligand for TLR7and/or TLR8,” and “TLR7 and/or signaling agonist” refer to a molecule,other than a compound disclosed herein, that interacts directly orindirectly with TLR7 and/or TLR8 through a TLR7 and/or TLR8 domain otherthan a TLR8 domain, and induces TLR7- and/or TLR8-mediated signaling. Incertain embodiments, a TLR7 and/or TLR8 ligand is a natural ligand,i.e., a TLR7 and/or TLR8 ligand that is found in nature. In certainembodiments, a TLR7 and/or TLR8 ligand refers to a molecule other than anatural ligand of TLR7 and/or TLR8, e.g., a molecule prepared by humanactivity.

As used herein, the term “modulator” is defined as a compound that bindsto and/or activates or inhibits the target with measurable affinity, ordirectly or indirectly affecting the normal regulation of the receptoractivity. In certain embodiments, a modulator has an EC₅₀ and/or bindingconstant of less about 50 μM, less than about 1 μM, less than about 500nM, less than about 100 nM, or less than about 10 nM.

As used herein, the term “agonist” refers to a compound that, incombination with a receptor (e.g., a TLR), can produce a cellularresponse. An agonist may be a ligand that directly binds to thereceptor. Alternatively, an agonist may combine with a receptorindirectly by, for example, (a) forming a complex with another moleculethat directly binds to the receptor, or (b) otherwise resulting in themodification of another compound so that the other compound directlybinds to the receptor. An agonist may be referred to as an agonist of aparticular TLR (e.g., a TLR7 and/or TLR8 agonist).

As used herein, the term “antagonist” refers to a compound that competeswith an agonist or inverse agonist for binding to a receptor, therebyblocking the action of an agonist or inverse agonist on the receptor.However, an antagonist has no effect on constitutive receptor activity.More specifically, an antagonist is a compound that inhibits theactivity of TLR7 or TLR8 at the TLR7 or TL8S receptor, respectively.

As used herein, the term “inhibit” refers to any measurable reduction ofbiological activity. Thus, as used herein, “inhibit” or “inhibition” maybe referred to as a percentage of a normal level of activity.

As used herein, the term “effective amount” of an active agent refers toan amount sufficient to elicit the desired biological response. As willbe appreciated by those of ordinary skill in this art, the effectiveamount of a compound of the invention may vary depending on such factorsas the desired biological endpoint, the pharmacokinetics of thecompound, the disease being treated, the mode of administration, and thepatient.

As used herein, the terms “treatment” or “treating” a disease ordisorder refers to a method of reducing, delaying or ameliorating such acondition before or after it has occurred. Treatment may be directed atone or more effects or symptoms of a disease and/or the underlyingpathology. The treatment can be any reduction and can be, but is notlimited to, the complete ablation of the disease or the symptoms of thedisease. As compared with an equivalent untreated control, suchreduction or degree of prevention is at least 5%, 10%, 20%, 40%, 50%,60%, 80%, 90%, 95%, or 100% as measured by any standard technique.

As used herein, the terms “prevent”, “preventing”, or “prevention” referto a method for precluding, delaying, averting, or stopping the onset,incidence, severity, or recurrence of a disease or condition. Forexample, a method is considered to be a prevention if there is areduction or delay in onset, incidence, severity, or recurrence of adisease or condition or one or more symptoms thereof in a subjectsusceptible to the disease or condition as compared to a subject notreceiving the method. The disclosed method is also considered to be aprevention if there is a reduction or delay in onset, incidence,severity, or recurrence of osteoporosis or one or more symptoms of adisease or condition in a subject susceptible to the disease orcondition after receiving the method as compared to the subject'sprogression prior to receiving treatment. Thus, the reduction or delayin onset, incidence, severity, or recurrence of osteoporosis can beabout a 5, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100%, or any amount ofreduction in between.

As used herein, a “pharmaceutically acceptable form” of a disclosedcompound includes, but is not limited to, pharmaceutically acceptablesalts, esters, hydrates, solvates, polymorphs, isomers, prodrugs, andisotopically labeled derivatives thereof. In one embodiment, a“pharmaceutically acceptable form” includes, but is not limited to,pharmaceutically acceptable salts, esters, prodrugs and isotopicallylabeled derivatives thereof. In some embodiments, a “pharmaceuticallyacceptable form” includes, but is not limited to, pharmaceuticallyacceptable isomers and stereoisomers, prodrugs and isotopically labeledderivatives thereof.

In certain embodiments, the pharmaceutically acceptable form is apharmaceutically acceptable salt. As used herein, the term“pharmaceutically acceptable salt” refers to those salts which are,within the scope of sound medical judgment, suitable for use in contactwith the tissues of subjects without undue toxicity, irritation,allergic response and the like, and are commensurate with a reasonablebenefit/risk ratio. Pharmaceutically acceptable salts are well known inthe art. For example, Berge et al. describes pharmaceutically acceptablesalts in detail in J. Pharmaceutical Sciences (1977) 66:1-19.Pharmaceutically acceptable salts of the compounds provided hereininclude those derived from suitable inorganic and organic acids andbases. Examples of pharmaceutically acceptable, nontoxic acid additionsalts are salts of an amino group formed with inorganic acids such ashydrochloric acid, hydrobromic acid, phosphoric acid, sulfuric acid andperchioric acid or with organic acids such as acetic acid, oxalic acid,maleic acid, tartaric acid, citric acid, succinic acid or malonic acidor by using other methods used in the art such as ion exchange. Otherpharmaceutically acceptable salts include adipate, alginate, ascorbate,aspartate, benzenesulfonate, besylate, benzoate, bisulfate, borate,butyrate, camphorate, camphorsulfonate, citrate, cyclopentanepropionate,digluconate, dodecylsulfate, ethanesulfonate, formate, fumarate,glucoheptonate, glycerophosphate, gluconate, hemisulfate, heptanoate,hexanoate, hydroiodide, 2-hydroxy-ethanesulfonate, lactobionate,lactate, laurate, lauryl sulfate, malate, maleate, malonate,methanesulfonate, 2-naphthalenesulfonate, nicotinate, nitrate, oleate,oxalate, palmitate, pamoate, pectinate, persulfate, 3-phenylpropionate,phosphate, picrate, pivalate, propionate, stearate, succinate, sulfate,tartrate, thiocyanate, p-toluenesulfonate, undecanoate, valerate salts,and the like. In some embodiments, organic acids from which salts can bederived include, for example, acetic acid, propionic acid, glycolicacid, pyruvic acid, oxalic acid, lactic acid, trifluoracetic acid,maleic acid, malonic acid, succinic acid, fumaric acid, tartaric acid,citric acid, benzoic acid, cinnamic acid, mandelic acid, methanesulfonicacid, ethanesulfonic acid, p-toluenesulfonic acid, salicylic acid, andthe like.

The salts can be prepared in situ during the isolation and purificationof the disclosed compounds, or separately, such as by reacting the freebase or free acid of a parent compound with a suitable base or acid,respectively. Pharmaceutically acceptable salts derived from appropriatebases include alkali metal, alkaline earth metal, ammonium and N⁺(C₁₋₄alkyl)₄ salts. Representative alkali or alkaline earth metal saltsinclude sodium, lithium, potassium, calcium, magnesium, iron, zinc,copper, manganese, aluminum, and the like. Further pharmaceuticallyacceptable salts include, when appropriate, nontoxic ammonium,quaternary ammonium, and amine cations formed using counterions such ashalide, hydroxide, carboxylate, sulfate, phosphate, nitrate, lower alkylsulfonate and aryl sulfonate. Organic bases from which salts can bederived include, for example, primary, secondary, and tertiary amines,substituted amines, including naturally occurring substituted amines,cyclic amines, basic ion exchange resins, and the like, such asisopropylamine, trimethylamine, diethylamine, triethylamine,tripropylamine, and ethanolamine. In some embodiments, thepharmaceutically acceptable base addition salt can be chosen fromammonium, potassium, sodium, calcium, and magnesium salts.

In certain embodiments, the pharmaceutically acceptable form is a“solvate” (e.g., a hydrate). As used herein, the term “solvate” refersto compounds that further include a stoichiometric or non-stoichiometricamount of solvent bound by non-covalent intermolecular forces. Thesolvate can be of a disclosed compound or a pharmaceutically acceptablesalt thereof. Where the solvent is water, the solvate is a “hydrate”.Pharmaceutically acceptable solvates and hydrates are complexes that,for example, can include 1 to about 100, or 1 to about 10, or 1 to about2, about 3 or about 4, solvent or water molecules. It will be understoodthat the term “compound” as used herein encompasses the compound andsolvates of the compound, as well as mixtures thereof.

In certain embodiments, the pharmaceutically acceptable form is aprodrug. As used herein, the term “prodrug” (or “pro-drug”) refers tocompounds that are transformed in vivo to yield a disclosed compound ora pharmaceutically acceptable form of the compound. A prodrug can beinactive when administered to a subject, but is converted in vivo to anactive compound, for example, by hydrolysis (e.g., hydrolysis in blood).In certain cases, a prodrug has improved physical and/or deliveryproperties over the parent compound. Prodrugs can increase thebioavailability of the compound when administered to a subject (e.g., bypermitting enhanced absorption into the blood following oraladministration) or which enhance delivery to a biological compartment ofinterest (e.g., the brain or lymphatic system) relative to the parentcompound. Exemplary prodrugs include derivatives of a disclosed compoundwith enhanced aqueous solubility or active transport through the gutmembrane, relative to the parent compound.

The prodrug compound often offers advantages of solubility, tissuecompatibility or delayed release in a mammalian organism (see, e.g.,Bundgard, H., Design of Prodrugs (1985), pp. 7-9, 21-24 (Elsevier,Amsterdam). A discussion of prodrugs is provided in Higuchi, T., et al.,“Prodrugs as Novel Delivery Systems,” A.C.S. Symposium Series, Vol. 14,and in Bioreversible Carriers in Drug Design, ed. Edward B. Roche,American Pharmaceutical Association and Pergamon Press, 1987, both ofwhich are incorporated in full by reference herein. Exemplary advantagesof a prodrug can include, but are not limited to, its physicalproperties, such as enhanced water solubility for parenteraladministration at physiological pH compared to the parent compound, orit can enhance absorption from the digestive tract, or it can enhancedrug stability for long-term storage.

Prodrugs commonly known in the art include well-known acid derivatives,such as, for example, esters prepared by reaction of the parent acidswith a suitable alcohol, amides prepared by reaction of the parent acidcompound with an amine, basic groups reacted to form an acylated basederivative, etc. Of course, other prodrug derivatives may be combinedwith other features disclosed herein to enhance bioavailability. Assuch, those of skill in the art will appreciate that certain of thepresently disclosed compounds having free amino, arnido, hydroxy orcarboxylic groups can be converted into prodrugs. Prodrugs includecompounds having an amino acid residue, or a polypeptide chain of two ormore (e.g., two, three or four) amino acid residues which are covalentlyjoined through peptide bonds to free amino, hydroxy or carboxylic acidgroups of the presently disclosed compounds. The amino acid residuesinclude the 20 naturally occurring amino acids commonly designated bythree letter symbols and also include 4-hydroxyproline, hydroxylysine,demosine, isodemosine, 3-methylhistidine, norvalin, beta-alanine,gamma-aminobutyric acid, citrulline homocysteine, homoserine, ornithineand methionine sulfone. Prodrugs also include compounds having acarbonate, carbamate, amide or alkyl ester moiety covalently bonded toany of the above substituents disclosed herein.

As used herein, the term “pharmaceutically acceptable” excipient,carrier, or diluent refers to a pharmaceutically acceptable material,composition or vehicle, such as a liquid or solid filler, diluent,excipient, solvent or encapsulating material, involved in carrying ortransporting the subject pharmaceutical agent from one organ, or portionof the body, to another organ, or portion of the body. Each carrier mustbe “acceptable” in the sense of being compatible with the otheringredients of the formulation and not injurious to the patient. Someexamples of materials which can serve as pharmaceutically-acceptablecarriers include: sugars, such as lactose, glucose and sucrose;starches, such as corn starch and potato starch; cellulose, and itsderivatives, such as sodium carboxymethyl cellulose, ethyl cellulose andcellulose acetate; powdered tragacanth; malt; gelatin; talc; excipients,such as cocoa butter and suppository waxes; oils, such as peanut oil,cottonseed oil, safflower oil, sesame oil, olive oil, corn oil andsoybean oil; glycols, such as propylene glycol; polyols, such asglycerin, sorbitol, mannitol and polyethylene glycol; esters, such asethyl oleate and ethyl laurate; agar; buffering agents, such asmagnesium hydroxide and aluminum hydroxide; alginic acid; pyrogen-freewater; isotonic saline; Ringer's solution; ethyl alcohol; phosphatebuffer solutions; and other non-toxic compatible substances employed inpharmaceutical formulations. Wetting agents, emulsifiers and lubricants,such as sodium lauryl sulfate, magnesium stearate, and polyethyleneoxide-polypropylene oxide copolymer as well as coloring agents, releaseagents, coating agents, sweetening, flavoring and perfuming agents,preservatives and antioxidants can also be present in the compositions.

As used herein, the terms “isolated” or “purified” refer to a materialthat is substantially or essentially free from components that normallyaccompany it in its native state. Purity and homogeneity are typicallydetermined using analytical chemistry techniques such as polyacrylamidegel electrophoresis or high-performance liquid chromatography.

As used herein, the term “subject” refers to any animal (e.g., amammal), including, but not limited to humans, non-human primates,rodents, and the like, which is to be the recipient of a particulartreatment. Typically, the terms “subject” and “patient” are usedinterchangeably herein in reference to a human subject.

As used herein, the term “low dosage” refers to at least 5% less (e.g.,at least 10%, 20%, 50%, 80%, 90%, or even 95%) than the lowest standardrecommended dosage of a particular compound formulated for a given routeof administration for treatment of any human disease or condition. Forexample, a low dosage of an agent that is formulated for administrationby inhalation will differ from a low dosage of the same agent formulatedfor oral administration.

As used herein, the term “high dosage” is meant at least 5% (e.g., atleast 10%, 20%, 50%, 100%, 200%, or even 300%) more than the higheststandard recommended dosage of a particular compound for treatment ofany human disease or condition.

Isotopically-labeled compounds are also within the scope of the presentdisclosure. As used herein, an “isotopically-labeled compound” or“isotope derivative” refers to a presently disclosed compound includingpharmaceutical salts and prodrugs thereof, each as described herein, inwhich one or more atoms are replaced by an atom having an atomic mass ormass number different from the atomic mass or mass number usually foundin nature. Examples of isotopes that can be incorporated into compoundspresently disclosed include isotopes of hydrogen, carbon, nitrogen,oxygen, phosphorous, fluorine and chlorine, such as ²H, ³H, ¹³C, ¹⁴C,¹⁵N, ¹⁸O, ¹⁷O, ³¹P, ³²P, ³⁵S, ¹⁸F, and ³⁶Cl, respectively.

By isotopically-labeling the presently disclosed compounds, thecompounds may be useful in drug and/or substrate tissue distributionassays. Tritiated (³H) and carbon-14 (¹⁴C) labeled compounds areparticularly preferred for their ease of preparation and detectability.Further, substitution with heavier isotopes such as deuterium (²H) canafford certain therapeutic advantages resulting from greater metabolicstability, for example increased in vivo half-life or reduced dosagerequirements and, hence, may be preferred in some circumstances.Isotopically labeled compounds presently disclosed, includingpharmaceutical salts, esters, and prodrugs thereof, can be prepared byany means known in the art. Benefits may also be obtained fromreplacement of normally abundant ¹²C with ¹³C. (See, WO 2007/005643, WO2007/005644, WO 2007/016361, and WO 2007/016431.)

For example, deuterium (²H) can be incorporated into a compounddisclosed herein for the purpose in order to manipulate the oxidativemetabolism of the compound by way of the primary kinetic isotope effect.The primary kinetic isotope effect is a change of the rate for achemical reaction that results from exchange of isotopic nuclei, whichin turn is caused by the change in ground state energies necessary forcovalent bond formation after this isotopic exchange. Exchange of aheavier isotope usually results in a lowering of the ground state energyfor a chemical bond and thus causes a reduction in the rate inrate-limiting bond breakage. If the bond breakage occurs in or in thevicinity of a saddle-point region along the coordinate of amulti-product reaction, the product distribution ratios can be alteredsubstantially. For explanation: if deuterium is bonded to a carbon atomat a non-exchangeable position, rate differences of k_(M)/k_(D)=2-7 aretypical. If this rate difference is successfully applied to a compounddisclosed herein that is susceptible to oxidation, the profile of thiscompound in vivo can be drastically modified and result in improvedpharmacokinetic properties.

When discovering and developing therapeutic agents, the person skilledin the art is able to optimize pharmacokinetic parameters whileretaining desirable in vitro properties. It is reasonable to assume thatmany compounds with poor pharmacokinetic profiles are susceptible tooxidative metabolism. In vitro liver microsomal assays currentlyavailable provide valuable information on the course of oxidativemetabolism of this type, which in turn permits the rational design ofdeuterated compounds of those disclosed herein with improved stabilitythrough resistance to such oxidative metabolism. Significantimprovements in the pharmacokinetic profiles of compounds disclosedherein are thereby obtained, and can be expressed quantitatively interms of increases in the in vivo half-life (t/2), concen-tra-tion atmaximum therapeutic effect (C_(max)), area under the dose response curve(AUC), and F; and in terms of reduced clearance, dose and materialscosts.

The following is intended to illustrate the above: a compound which hasmultiple potential sites of attack for oxidative metabolism, for examplebenzylic hydrogen atoms and hydrogen atoms bonded to a nitrogen atom, isprepared as a series of analogues in which various combinations ofhydrogen atoms are replaced by deuterium atoms, so that some, most orall of these hydrogen atoms have been replaced by deuterium atoms.Half-life determinations enable favorable and accurate determination ofthe extent of the extent to which the improvement in resistance tooxidative metabolism has improved. In this way, it is determined thatthe half-life of the parent compound can be extended by up to 100% asthe result of deuterium-hydrogen exchange of this type.

Deuterium-hydrogen exchange in a compound disclosed herein can also beused to achieve a favorable modification of the metabolite spectrum ofthe starting compound in order to diminish or eliminate undesired toxicmetabolites. For example, if a toxic metabolite arises through oxidativecarbon-hydrogen (C—H) bond cleavage, it can reasonably be assumed thatthe deuterated analogue will greatly diminish or eliminate production ofthe unwanted metabolite, even if the particular oxidation is not arate-determining step. Further information on the state of the art withrespect to deuterium-hydrogen exchange may be found, for example inHanzlik et al., J. Org. Chem. 55, 3992-3997, 1990, Reider et al., J.Org. Chem. 52, 3326-3334, 1987, Foster, Adv. Drug Res. 14, 1-40, 1985,Gillette et al, Biochemistry 33(10) 2927-2937, 1994, and Jarman et al.Carcinogenesis 16(4), 683-688, 1993.

Compounds of the present invention are, subsequent to their preparation,preferably isolated and purified to obtain a composition containing anamount by weight equal to or greater than 95% (“substantially pure”),which is then used or formulated as described herein. In certainembodiments, the compounds of the present invention are more than 99%pure.

Combinations of substituents and variables envisioned by this inventionare only those that result in the formation of stable compounds. Theterm “stable”, as used herein, refers to compounds which possessstability sufficient to allow manufacture and which maintains theintegrity of the compound for a sufficient period of time to be usefulfor the purposes detailed herein (e.g., therapeutic or prophylacticadministration to a subject).

The recitation of a listing of chemical groups in any definition of avariable herein includes definitions of that variable as any singlegroup or combination of listed groups. The recitation of an embodimentfor a variable herein includes that embodiment as any single embodimentor in combination with any other embodiments or portions thereof.

DETAILED DESCRIPTION OF THE INVENTION

The invention provides novel imidazoquinoline amine derivatives, whichare agonists of TLRs, in particular TLR7 and/or TLR8, pharmaceuticalcompositions thereof, and methods of treatment, reduction or preventionof certain diseases or conditions mediated by or associated with TLR7and/or TLR8, e.g., graft rejection, autoimmunity, inflammation allergy,asthma, infection, sepsis, cancer and immunodeficiency, or relateddiseases and conditions.

In one aspect, the invention generally relates to a compound having thestructural formula (I):

wherein,

R¹ is a C₁-C₈ (e.g., C₁-C₄, C₄-C₆, C₆-C₈) alkyl group;

R² is (CH₂)_(m), wherein m is an integer selected from 1 to 8 (e.g., 1,2, 3, 4, 5, 6, 7, 8);

L is a linking moiety; and

R³ is a C₁-C₃₂ (e.g., C₁-C₁₆, C₁₆-C₃₂, C₁₆-C₂₄) alkyl group;

or a pharmaceutically acceptable form or an isotope derivative thereof.

In certain embodiments, R¹ is a C₃-C₆ (e.g., C₃, C₄, C₅, C₆) alkylgroup, m is an integer selected from 3 to 8 (e.g., 3, 4, 5, 6, 7, 8),and R³ is a C₁₂-C₃₂ (e.g., C₁-C₁₆, C₁₆-C₃₂, C₁₆-C₂₄) alkyl group.

In certain embodiments, R¹ is a C₄ alkyl group, having the structuralformula:

In certain embodiments, R¹ is a C₄ alkyl group and m is 4, having thestructural formula:

In certain embodiments, R² is a C₁₄-C₂₀ (e.g., C₁₄-C₁₆, C₁₆-C₁₈,C₁₈-C₂₀) alkyl group.

In certain embodiments, L comprises an amino group.

In certain embodiments, L is an acyclic group.

In certain embodiments, L comprises a 3- to 7-(e.g., 3-, 4-, 5-, 6-, 7-)membered ring.

In certain embodiments, L is selected from:

It is noted that the exemplary linkers (L) may be connected to the restof the compound such that L is boned to R² on the left and to R³ on theright, or may be connected to the rest of the compound such that L isbonded to R² on the right and to R³ on the left.

Exemplary compounds of the invention include, but are not limited to,those listed in Table 1, or a pharmaceutically acceptable form or anisotope derivative thereof.

TABLE 1 Exemplary Compounds

1

2

3

4

5

6

7

8

9

10

11

12

In certain embodiments, the compound is

or a pharmaceutically acceptable form or an isotope derivative thereof.

In certain embodiments, the compound is

or a pharmaceutically acceptable form or an isotope derivative thereof.

In certain embodiments, the compound is

or a pharmaceutically acceptable form or an isotope derivative thereof.

In certain embodiments, the compound is

or a pharmaceutically acceptable form or an isotope derivative thereof.

In certain embodiments, the compound is

or a pharmaceutically acceptable form or an isotope derivative thereof.

In certain embodiments, the compound is

or a pharmaceutically acceptable form or an isotope derivative thereof.

In certain embodiments, the compound is

or a pharmaceutically acceptable form or an isotope derivative thereof.

In certain embodiments, the compound is

or a pharmaceutically acceptable form or an isotope derivative thereof.

In certain embodiments, the compound is

or a pharmaceutically acceptable form or an isotope derivative thereof.

In certain embodiments, the compound is

or a pharmaceutically acceptable form or an isotope derivative thereof.

In certain embodiments, the compound is

In certain embodiments, the compound is

In another aspect, the invention generally relates to a pharmaceuticalcomposition comprising a compound disclosed herein.

In yet another aspect, the invention generally relates to apharmaceutical composition comprising an amount of a compound having thestructural formula (I):

wherein,

R¹ is a C₁-C₈ (e.g., C₁-C₄, C₄-C₆, C₆-C₈) alkyl group;

R² is (CH₂)_(m), wherein m is an integer selected from 1 to 8 (e.g., 1,2, 3, 4, 5, 6, 7, 8);

L is a linking moiety; and

R³ is a C₁-C₃₂ (e.g., C₁-C₁₆, C₁₆-C₃₂, C₁₆-C₂₄) alkyl group;

or a pharmaceutically acceptable form or an isotope derivative thereof,effective to treat, prevent, or reduce one or more diseases ordisorders, in a mammal, including a human, and a pharmaceuticallyacceptable excipient, carrier, or diluent.

In certain embodiments, the pharmaceutical composition disclosed hereinis effective to treat, reduce or prevent an autoimmune disease, or arelated disease or disorder.

In certain embodiments, the pharmaceutical composition disclosed hereinis effective to treat, reduce or prevent graft rejection, or a relateddisease or disorder.

In certain embodiments, the pharmaceutical composition disclosed hereinis effective to treat, reduce or prevent an allergy, or a relateddisease or disorder.

In certain embodiments, the pharmaceutical composition disclosed hereinis effective to treat, reduce or prevent an immunodeficiency, or arelated disease or disorder.

In certain embodiments, the pharmaceutical composition disclosed hereinis effective to treat, reduce or prevent infection, sepsis, or a relateddisease or disorder.

In certain embodiments, the pharmaceutical composition disclosed hereinis effective to treat, reduce or prevent cancer, or a related disease ordisorder.

In yet another aspect, the invention generally relates to a unit dosageform comprising a compound disclosed herein.

In yet another aspect, the invention generally relates to a unit dosageform comprising a pharmaceutical composition disclosed herein.

In yet another aspect, the invention generally relates to a method fortreating, reducing, or preventing a disease or disorder, comprisingadministering to a subject in need thereof a pharmaceutical compositioncomprising a compound having the structural formula (I):

wherein,

R¹ is a C₁-C₈ alkyl group;

R² is (CH₂)_(m), wherein m is an integer selected from 1 to 8 (e.g., 1,2, 3, 4, 5, 6, 7, 8);

L is a linking moiety; and

R³ is a C₁-C₃₂ (e.g., C₁-C₁₆, C₁₆-C₃₂, C₁₆-C₂₄) alkyl group;

or a pharmaceutically acceptable form or an isotope derivative thereof,effective to treat, prevent, or reduce one or more of autoimmunediseases, graft rejection, allergies, immunodeficiency, infection,sepsis, cancer, or a related disease or disorder thereof, in a mammal,including a human, and a pharmaceutically acceptable excipient, carrier,or diluent.

In certain embodiments, the method is to treat, reduce or prevent anautoimmune disease, or a related disease or disorder.

In certain embodiments, the method is to treat, reduce or prevent graftrejection, or a related disease or disorder.

In certain embodiments, the method is effective to treat, reduce orprevent allergy, or a related disease or disorder.

In certain embodiments, the method is effective to treat, reduce orprevent an immunodeficiency, or a related disease or disorder.

In certain embodiments, the method is effective to treat, reduce orprevent infection and/or sepsis, or a related disease or disorder

In certain embodiments, the method is effective to treat, reduce orprevent cancer, or a related disease or disorder.

In yet another aspect, the invention generally relates to a method formodulating immune response, comprising administering to a subject inneed thereof a pharmaceutical composition comprising a compounddisclosed herein.

In yet another aspect, the invention generally relates to a method formodulating TLR7- and/or TLR8-mediated signaling, comprisingadministering to a subject in need thereof a pharmaceutical compositioncomprising a compound disclosed herein.

In yet another aspect, the invention generally relates to a method forof treating or reducing a condition or disorder treatable by modulationof TLR7- and/or TLR8-mediated cellular activities, comprisingadministering to a subject in need thereof a pharmaceutical compositioncomprising a compound disclosed herein.

In yet another aspect, the invention generally relates to a method fortreating, reducing, or preventing a disease or disorder, comprisingadministering to a subject in need thereof a pharmaceutical compositioncomprising a compound disclosed herein, wherein the disease or disorderis autoimmune diseases, graft rejection, allergies, immunodeficiency,infection, sepsis, cancer, or a related disease or disorder.

In certain embodiments, the compound is an agonist of TLR7.

In certain embodiments, the compound is an agonist of TLR8.

In yet another aspect, the invention generally relates to use of acompound disclosed herein for treating, reducing or preventing a diseaseor disorder.

In yet another aspect, the invention generally relates to use of acompound disclosed herein and a pharmaceutically acceptable excipient,carrier, or diluent, in preparation of a medicament for treating,reducing or preventing a disease or disorder.

In certain embodiments, the disease or disorder is mediated by orassociated with TLR7- and/or TLR8-mediated signaling.

In certain embodiments, the compound disclosed herein is used to treat,reduce or prevent a disease or disorder selected from autoimmunediseases, graft rejection, allergies, immunodeficiency, infection,sepsis, cancer, or a related disease or disorder thereof.

In certain embodiments, the compound disclosed herein is used to treat,reduce or prevent an autoimmune disease, or a related disease ordisorder.

In certain embodiments, the compound disclosed herein is used to treat,reduce or prevent graft rejection, or a related disease or disorder.

In certain embodiments, the compound disclosed herein is used to treat,reduce or prevent allergy, or a related disease or disorder.

In certain embodiments, the compound disclosed herein is used to treat,reduce or prevent immunodeficiency, or a related disease or disorder.

In certain embodiments, the compound disclosed herein is used to treat,reduce or prevent infection and/or sepsis, or a related disease ordisorder

In certain embodiments, the compound disclosed herein is used to treat,reduce or prevent cancer, or a related disease or disorder.

In certain embodiments, the compound disclosed herein is used as vaccineadjuvants and to prevent, inhibit or treat a variety of disorders likeinflammation, cancer and microbial infections.

The compounds according to the invention may be used as agonists ofTLR's, specifically for TLR7 and TLR8.

The compounds according to the invention may provide methods formodulating TLR7- and/or TLR8-mediated signaling. The methods of theinvention are useful, for example, when it is desirable to alter TLR7-and/or TLR8-mediated signaling in response to a suitable TLR7 and/orTLR8 ligand or a TLR7 and/or TLR8 signaling agonist.

The compounds according to the invention may be used in the treatment orprevention of conditions and disorders include, but are not limited to,cancer, immune complex-associated diseases, inflammatory disorders,immunodeficiency, graft rejection, graft-versus-host disease, allergies,asthma, infection, and sepsis. More specifically, methods useful in thetreatment of conditions involving autoimmunity, inflammation, allergy,asthma, graft rejection. Alternatively, methods useful in the treatmentof conditions involving infection, cancer, and immunodeficiencygenerally will employ compounds disclosed herein that augment TLR7-and/or TLR8-mediated signaling in response to a suitable TLR7 and/orTLR8 ligand. In some instances, the compositions can be used to inhibitor promote TLR 7- and/or TLR8-mediated signaling in response to a TLR7and/or TLR8 ligand or signaling agonist. In other instance, thecompositions can be used to inhibit or promote TLR7- and/orTLR8-mediated immune-stimulation in a subject.

The compounds according to the inventions may also be used in thetreatment or prevention of hepatocarcinomas, cholangiocarcinoma andmalignant mesothelioma, pancreatic cancer, head and neck cancer, andhaemoangioma.

The compounds according to the inventions may also be used in thetreatment or prevention treating obesity in a patient. The inventionprovides a method of treating type II diabetes in a patient in need oftreatment comprising administering to the patient an effective amount ofa compound disclosed herein or a pharmaceutically acceptable saltthereof. Preferably the patient is a human. The present inventionprovides a method for treating nonalcoholic steatohepatitis in a patientin need of such treatment, comprising administering to the patient aneffective amount of a compound disclosed herein or a pharmaceuticallyacceptable salt thereof.

The present invention provides use of a compound disclosed herein, or apharmaceutically acceptable salt thereof, in the manufacture of amedicament for the treatment of obesity. The present invention providesthe use of a compound disclosed herein, or a pharmaceutically acceptablesalt thereof, in the manufacture of a medicament for treatment toprovide therapeutic weight loss.

The amount of compound in compositions of this invention is such that iseffective to measurably modulate TLR's, in particular TLR7 and/or TLR8,or a mutant thereof, in a biological sample or in a patient. In certainembodiments, the amount of compound in compositions of this invention issuch that is effective to measurably modulate TLR's, or a mutantthereof, in a biological sample or in a patient. In certain embodiments,a composition of this invention is formulated for administration to apatient in need of such composition.

Solid dosage forms for oral administration include capsules, tablets,pills, powders, and granules. In such solid dosage forms, the compoundsdescribed herein or derivatives thereof are admixed with at least oneinert customary excipient (or carrier) such as sodium citrate ordicalcium phosphate or (i) fillers or extenders, as for example,starches, lactose, sucrose, glucose, mannitol, and silicic acid, (ii)binders, as for example, carboxymethylcellulose, alginates, gelatin,polyvinylpyrrolidone, sucrose, and acacia, (iii) humectants, as forexample, glycerol, (iv) disintegrating agents, as for example,agar-agar, calcium carbonate, potato or tapioca starch, alginic acid,certain complex silicates, and sodium carbonate, (v) solution retarders,as for example, paraffin, (vi) absorption accelerators, as for example,quaternary ammonium compounds, (vii) wetting agents, as for example,cetyl alcohol, and glycerol monostearate, (viii) adsorbents, as forexample, kaolin and bentonite, and (ix) lubricants, as for example,talc, calcium stearate, magnesium stearate, solid polyethylene glycols,sodium lauryl sulfate, or mixtures thereof. In the case of capsules,tablets, and pills, the dosage forms may also comprise buffering agents.Solid compositions of a similar type may also be employed as fillers insoft and hard-filled gelatin capsules using such excipients as lactoseor milk sugar as well as high molecular weight polyethyleneglycols, andthe like. Solid dosage forms such as tablets, dragees, capsules, pills,and granules can be prepared with coatings and shells, such as entericcoatings and others known in the art.

Liquid dosage forms for oral administration include pharmaceuticallyacceptable emulsions, solutions, suspensions, syrups, and elixirs. Inaddition to the active compounds, the liquid dosage forms may containinert diluents commonly used in the art, such as water or othersolvents, solubilizing agents, and emulsifiers, such as for example,ethyl alcohol, isopropyl alcohol, ethyl carbonate, ethyl acetate, benzylalcohol, benzyl benzoate, propyleneglycol, 1,3-butyleneglycol,dimethylformamide, oils, in particular, cottonseed oil, groundnut oil,corn germ oil, olive oil, castor oil, sesame oil, glycerol,tetrahydrofurfuryl alcohol, polyethyleneglycols, and fatty acid estersof sorbitan, or mixtures of these substances, and the like. Besides suchinert diluents, the composition can also include additional agents, suchas wetting, emulsifying, suspending, sweetening, flavoring, or perfumingagents.

Materials, compositions, and components disclosed herein can be usedfor, can be used in conjunction with, can be used in preparation for, orare products of the disclosed methods and compositions. It is understoodthat when combinations, subsets, interactions, groups, etc. of thesematerials are disclosed that while specific reference of each variousindividual and collective combinations and permutations of thesecompounds may not be explicitly disclosed, each is specificallycontemplated and described herein. For example, if a method is disclosedand discussed and a number of modifications that can be made to a numberof molecules including in the method are discussed, each and everycombination and permutation of the method, and the modifications thatare possible are specifically contemplated unless specifically indicatedto the contrary. Likewise, any subset or combination of these is alsospecifically contemplated and disclosed. This concept applies to allaspects of this disclosure including, but not limited to, steps inmethods using the disclosed compositions. Thus, if there are a varietyof additional steps that can be performed, it is understood that each ofthese additional steps can be performed with any specific method stepsor combination of method steps of the disclosed methods, and that eachsuch combination or subset of combinations is specifically contemplatedand should be considered disclosed.

Compositions of the present invention are administered orally,parenterally, by inhalation spray, topically, rectally, nasally,buccally, vaginally or via an implanted reservoir. The term “parenteral”as used herein includes subcutaneous, intravenous, intramuscular,intra-articular, intra-synovial, intrasternal, intrathecal,intrahepatic, intralesional, intratumoral and intracranial injection orinfusion techniques.

Pharmaceutically acceptable compositions of this invention are orallyadministered in any orally acceptable dosage form. Exemplary oral dosageforms are capsules, tablets, aqueous suspensions or solutions. In thecase of tablets for oral use, carriers commonly used include lactose andcorn starch. Lubricating agents, such as magnesium stearate, are alsotypically added. For oral administration in a capsule form, usefuldiluents include lactose and dried cornstarch. When aqueous suspensionsare required for oral use, the active ingredient is combined withemulsifying and suspending agents. If desired, certain sweetening,flavoring or coloring agents are optionally also added.

Alternatively, pharmaceutically acceptable compositions of thisinvention are administered in the form of suppositories for rectaladministration. These can be prepared by mixing the agent with asuitable non-irritating excipient that is solid at room temperature butliquid at rectal temperature and therefore will melt in the rectum torelease the drug. Such materials include cocoa butter, beeswax andpolyethylene glycols.

Pharmaceutically acceptable compositions of this invention are alsoadministered topically, especially when the target of treatment includesareas or organs readily accessible by topical application, includingdiseases of the eye, the skin, or the lower intestinal tract. Suitabletopical formulations are readily prepared for each of these areas ororgans.

Topical application for the lower intestinal tract can be effected in arectal suppository formulation (see above) or in a suitable enemaformulation. Topically-transdermal patches are also used.

For topical applications, provided pharmaceutically acceptablecompositions are formulated in a suitable ointment containing the activecomponent suspended or dissolved in one or more carriers. Exemplarycarriers for topical administration of compounds of this aremineral oil,liquid petrolatum, white petrolatum, propylene glycol, polyoxyethylene,polyoxypropylene compound, emulsifying wax and water. Alternatively,provided pharmaceutically acceptable compositions can be formulated in asuitable lotion or cream containing the active components suspended ordissolved in one or more pharmaceutically acceptable carriers. Suitablecarriers include, but are not limited to, mineral oil, sorbitanmonostearate, polysorbate 60, cetyl esters wax, cetearyl alcohol,2-octyldodecanol, benzyl alcohol and water.

Pharmaceutically acceptable compositions of this invention areoptionally administered by nasal aerosol or inhalation. Suchcompositions are prepared according to techniques well-known in the artof pharmaceutical formulation and are prepared as solutions in saline,employing benzyl alcohol or other suitable preservatives, absorptionpromoters to enhance bioavailability, fluorocarbons, and/or otherconventional solubilizing or dispersing agents.

Most preferably, pharmaceutically acceptable compositions of thisinvention are formulated for oral administration. Such formulations maybe administered with or without food. In some embodiments,pharmaceutically acceptable compositions of this invention areadministered without food. In other embodiments, pharmaceuticallyacceptable compositions of this invention are administered with food.

The amount of compounds of the present invention that are optionallycombined with the carrier materials to produce a composition in a singledosage form will vary depending upon the host treated, the particularmode of administration. Preferably, provided compositions should beformulated so that a dosage of between 0.01-100 mg/kg body weight/day ofthe compound can be administered to a patient receiving thesecompositions.

It should also be understood that a specific dosage and treatmentregimen for any particular patient will depend upon a variety offactors, including the activity of the specific compound employed, theage, body weight, general health, sex, diet, time of administration,rate of excretion, drug combination, and the judgment of the treatingphysician and the severity of the particular disease being treated. Theamount of a compound of the present invention in the composition willalso depend upon the particular compound in the composition.

The following examples are meant to be illustrative of the practice ofthe invention and not limiting in any way.

EXAMPLES

The below Examples describe certain exemplary embodiments of compoundsprepared according to the disclosed invention. It will be appreciatedthat the following general methods, and other methods known to one ofordinary skill in the art, can be applied to compounds and subclassesand species thereof, as disclosed herein.

¹H NMR was recorded on a Bruker 400 MHz spectrometer, using residualsignal of deuterated solvent as internal reference. Chemical shifts (δ)are reported in ppm relative to the residual solvent signal (δ=2.50 ppmfor 1H NMR in DMSO-d6; δ=3.31 ppm for 1H NMR in MeOD-d4).

LCMS was taken on a quadrupole Mass Spectrometer on Shimadzu LC/MS2020Series (SunFire C18 3.5 μm 50*4.6 mm) operating in ES (+) or (−)ionization mode; T=40° C.; flow rate=2.0 mL/min; detected wavelength:254 nm.

HPLC was performed under conditions: (Flash: Welchrom C18 5 um 4.6×150mm); Wavelength 254 nm and 214 nm; Mobile phase: A water (0.03% TFA); BMeCN (0.03% TFA); Flow rate: 1 mL/min; Injection volume: 2 μL; Run time:16 min; Equilibration: 6 min.

Prep-HPLC was performed under conditions: (Flash: Welchrom C18 250×19mm); Wavelength 254 nm and 214 nm; Mobile phase: A water (0.1% HCl); BMeCN; Flow rate: 20 mL/min; Injection volume: 0.5 mL; Run time: 18 min;Equilibration: 2 min.

Example 1.N1-(4-((4-amino-2-butyl-1H-imidazo[4,5-c]quinolin-1-yl)oxy)butyl)-N2-heptadecyloxalamide(1)

Step 1: To a stirred solution of 1-1 (22.0 g, 247 mmol) in DCM (300 mL)under argon atmosphere were added pyridine (29 mL, 371 mmol) and benzylchloroformate (42.3 g, 247 mmol, in 250 mL DCM) at 0° C.; the mixturewas warmed to RT and stirred for 16 h. The reaction mixture was dilutedwith 1N HCl (400 mL) at 0° C. The organic layer was washed with brine(400 mL), dried over sodium sulfate, filtered and concentrated in vacuoto afford 1-2 (29 g, yield: 52.7%) as a light-yellow solid. ¹H NMR (400MHz, CDCl3) δ 7.38-7.31 (m, 5H), 5.09 (s, 2H), 3.75-3.55 (m, 2H),3.29-3.16 (m, 2H), 1.58-1.55 (m, 4H).

Step 2: A solution of N-hydroxyphthalimide (23.3 g, 143 mmol), benzyl(4-hydroxybutyl)carbamate 1-2 (29.0 g, 130 mmol) and triphenylphosphine(51.0 g, 195 mmol) in dichloromethane (600 mL) was chilled in an icebath and a solution of diisopropylazodicarboxylate (DIAD, 39.4 g, 195mmol) in dichloromethane (250 mL) was slowly added with stirring. Thereaction mixture was stirred at 0° C. for 1 h and warm to RT, stirredfor 4 h. The reaction was completed by TLC(PE/EA=2:1). The reaction wasconcentrated under reduced pressure, the residue was purified by columnchromatography (PE/EA=2:1) to give 1-3 (32 g, yield: 68.2%) as a whitesolid. ¹H NMR (400 MHz, CDCl3) δ 7.84-7.81 (m, 2H), 7.77-7.72 (m, 2H),7.38-7.28 (m, 5H), 5.09 (s, 2H), 4.23 (t, J=5.2 Hz, 2H), 3.34-3.29 (m,2H), 1.84-1.75 (m, 4H).

Step 3: To a solution of 1-3 (22.0 g, 59.8 mmol) in EtOH (350 mL) wasadded hydrazine (6.2 g, in 11.5 mL water) and the reaction was stirredat RT overnight. The reaction was cooled in the freezer and theresulting solid was removed by filtration. The solid was washed withethanol (400 mL). The combined filtrate was concentrated under reducedpressure and diethyl ether (400 mL) was added. Insoluble impurities wereremoved by filtration and 3.0 M HCl in dioxane (100 mL) was added to thesolution. A precipitate formed immediately. The mixture was stirred atRT for 16 h, the solid was recovered by filtration and dried undervacuum to give 1-4 (12 g, yield: 85.7%) as a white solid. ¹H NMR (400MHz, DMSO) δ 7.36-7.27 (m, 5H), 5.35 (s, 2H), 5.09 (s, 2H), 4.91 (s,1H), 3.66 (t, J=6.2 Hz, 2H), 3.24-3.19 (m, 2H), 1.62-1.55 (m, 4H). MSm/z (ESI): 239.1 [M+H]⁺.

Step 4: To a solution of 1-4 (10.0 g, 38.2 mmol) in isopropanol (20 mL)was added 1-4a (11.8 g, 49.6 mmol) and TEA (7.72 g, 76.4 mmol), thereaction mixture was stirred at 100° C. for 16 h under argon atmosphere.The mixture was concentrated under vacuum, the residue was purified bycolumn chromatography (DCM/MeOH=10:1) to give 1-5 (14.5 g, yield: 85.3%)as a yellow oil. ¹H NMR (400 MHz, CDCl₃) δ 9.25 (s, 1H), 8.76 (d, J=4.2Hz, 1H), 8.49-8.37 (m, 1H), 7.87 (d, J=2.0 Hz, 2H), 7.38-7.31 (m, 5H),5.12 (s, 2H), 4.58-4.35 (m, 2H), 3.44-3.35 (m, 2H), 3.11-3.00 (m, 2H),2.18-2.06 (m, 2H), 2.02-1.94 (m, 2H), 1.92-1.82 (m, 2H), 1.03 (t, J=6.4Hz, 3H).

Step 5: To a solution of 1-5 (13.5 g, 30.3 mmol) in DCM (300 mL) wasadded 30% H₂O₂ (67.5 mL) and m-CPBA (12.3 g, 60.6 mmol) at 0° C., thereaction mixture was allowed to stirred at RT for 16 h under argonatmosphere. LCMS (MC18-197-066-1) showed 55% starting material remained.m-CPBA (6.2 g, 15.2 mmol) was added to the mixture, then stirred at r.t.for 2 h; LCMS showed 38% starting material remained. m-CPBA (12.3 g,60.6 mmol) was added to the mixture, then stirred at RT for 16 h; LCMSshowed 17% starting material remained. Water (200 mL) added to themixture, and extracted with DCM (200 mL*2), the combined organic layerwas washed with sodium carbonate solution (400 mL) and brine (400 mL),dried over sodium sulfate, filtered and concentrated in vacuum to give1-6 (13 g, crude) which was used in next step directly. MS m/z (ESI):463.2 [M+H]⁺.

Step 6: To a solution of 1-6 (13 g, 28.1 mmol) in DCM (300 mL) was addedammonium hydroxide (13 mL of a28-30 percent aqueous solution) at 0° C.,a solution of TsCl (13.4 g, 70.3 mmol) dissolved in 50 mLdichloromethane was slowly added with vigorous stirring. The coolingbath was removed and the reaction was stirred for an additional 16 h.The desired product was detected by LCMS. The mixture was added water(300 mL) and extracted with DCM (200 mL*2), the combined organic layerwas washed with sodium carbonate solution (300 mL*2) and brine (400mL*2), dried over sodium sulfate, filtered and concentrated in vacuo,the residue was purified by column chromatography (DCM/MeOH=10:1) toafford 1-7 (7.0 g, yield: 54.3%) as a yellow oil. ¹H NMR (400 MHz,CDCl3) δ 8.11 (d, J=8.0 Hz, 1H), 7.94 (d, J=8.4 Hz, 1H), 7.65-7.61 (m,1H), 7.49-7.45 (m, 1H), 7.40-7.36 (m, 5H), 5.14 (s, 2H), 4.96 (s, 1H),4.36 (t, J=6.0 Hz, 2H), 3.41-3.36 (m, 2H), 2.96 (t, J=7.6 Hz, 2H),2.05-2.00 (m, 2H), 1.93-1.83 (m, 4H), 1.53-1.47 (m, 2H), 1.02 (t, J=7.2Hz, 3H). MS m/z (ESI): 462.6 [M+H]+.

Step 7: A solution of 1-7 (7.0 g, 15.2 mmol) in con.HCl (20 mL) wasstirred at 80° C. overnight. LCMS showed the reaction was completed. Themixture was cooled to RT, added water (30 mL), adjusted pH to 9-10 withsodium carbonate solid, extracted with DCM/MeOH=10:1 (50 mL*6). Thecombined organic layer was dried by sodium sulfate, filtered, andconcentrated in vacuo to give 1-8 (5.0 g, crude) as a yellow oil whichwas used in next step directly. ¹H NMR (400 MHz, CDCl₃) δ 8.10 (d, J=8.0Hz, 1H), 7.79 (d, J=8.4 Hz, 1H), 7.54 (d, J=7.6 Hz, 1H), 7.34 (t, J=7.6Hz, 1H), 5.36 (s, 2H), 4.32 (t, J=6.8 Hz, 2H), 2.98-2.92 (m, 2H), 2.86(t, J=6.8 Hz, 2H), 2.02 (dd, J=15.2, 6.8 Hz, 2H), 1.91 (dd, J=15.2, 7.4Hz, 2H), 1.78-1.73 (m, 2H), 1.71-1.62 (m, 2H), 1.52-1.46 (m, 2H), 1.00(t, J=7.2 Hz, 3H). MS m/z (ESI): 328.2 [M+H]⁺.

Step 8: To a solution of 1-9a (0.51 mL, 5.88 mmol) in dry DCM (20 mL)was added 1-9 (1.0 g, 3.92 mmol) in dry DCM (20 mL) dropwise at 0° C.,then the mixture was stirred at 0° C. for 1 h, DIEA (507 mg, 3.92 mmol)was added dropwise, the mixture was stirred at room temperature for 4 h.The mixture was concentrated in vacuo to give the desired product 1-10(1.0 g, crude), which was used in next step directly.

Step 9: To a solution of 1-10 (1.0 g, crude) in dry DCM (10 mL) wasadded 1-8 (100 mg, 0.306 mmol) in dry DCM (10 mL) dropwise at 0° C.,DIEA (79 mg, 0.612 mmol) was added dropwise, the mixture was stirred atRT for 16 h. he mixture was filtered, the filtrate was concentrated invacuo, the residue was purified by prep-TLC (DCM/MeOH=10:1) to givecompound 1 (39.18 mg, yield: 20.1%) as a yellow solid. ¹H NMR (400 MHz,DMSO-d6) δ 8.87 (t, J=6.0 Hz, 1H), 8.70 (t, J=6.0 Hz, 1H), 8.13 (d,J=8.0 Hz, 1H), 7.97 (s, 2H), 7.74 (d, J=8.4 Hz, 1H), 7.63 (t, J=7.6 Hz,1H), 7.48 (t, J=7.6 Hz, 1H), 4.38 (t, J=6.4 Hz, 2H), 3.28-3.23 (m, 2H),3.12 (dd, J=13.4, 6.8 Hz, 2H), 2.98 (t, J=7.6 Hz, 2H), 1.95-1.87 (m,2H), 1.84 (dd, J=15.0, 7.6 Hz, 2H), 1.76 (dd, J=15.0, 7.6 Hz, 2H), 1.43(dd, J=14.9, 7.4 Hz, 4H), 1.22 (br.s, 28H), 0.94 (t, J=7.6 Hz, 3H), 0.84(d, J=13.6 Hz, 3H). MS m/z (ESI) 637.4 [M+H]⁺.

Example 2.3-((4-((4-amino-2-butyl-1H-imidazo[4,5-c]quinolin-1-yl)oxy)butyl)amino)-4-(heptadecylamino)cyclobut-3-ene-1,2-dione(2)

Step 1: To a solution of 2-1 (200 mg, 1.177 mmol) in MeOH (6 mL) wasadded 2-2 (300 mg, 1177 mmol) in MeOH (10 mL) at 0° C. dropwise, thenthe mixture was stirred at RT for 4 h. TLC (PE/EA=2:1) showed thereaction was completed. The mixture was concentrated in vacuo to givethe desired product 2-3 (520 mg, yield: 91.4%) as a white solid. ¹H NMR(400 MHz, CDCl₃) δ 4.82-4.77 (m, 2H), 3.43-3.41 (m, 2H), 1.64-1.59 (m,3H), 1.46 (t, J=6.8 Hz, 2H), 1.32-1.26 (m, 28H), 0.88 (t, J=6.8 Hz, 3H).

Step 2: To a solution of 2-3 (198 mg, 0.413 mmol) and 1-8 (90 mg, 0.275mmol) in MeOH (10 mL) was added DIEA (71 mg, 0.55 mmol), the mixture wasstirred at RT for 16 h. The mixture was concentrated in vacuo, theresidue was purified by prep-HPLC (FA) to give the desired product 2 (FAsalt), which was neutralized with sodium carbonate solution (10 mL) togive the product 2 as free base (20.8 mg, yield: 10.3%) as a lightyellow solid. ¹H NMR (400 MHz, CDCl₃, DMSO-d6) δ 7.92 (d, J=6.4 Hz, 1H),7.60 (d, J=6.8 Hz, 1H), 7.36 (s, 1H), 7.19 (d, J=6.4 Hz, 1H), 6.91 (s,1H), 6.79 (s, 1H), 5.48 (s, 2H), 4.21 (d, J=16.0 Hz, 2H), 3.62 (d, J=2.0Hz, 2H), 3.48 (d, J=1.9 Hz, 2H), 2.82-2.76 (m, 2H), 1.94-1.86 (m, 2H),1.80-1.69 (m, 4H), 1.47-1.40 (m, 2H), 1.34 (d, J=6.4 Hz, 2H), 1.10(br.s, 26H), 0.87-0.83 (m, 2H), 0.76-0.67 (m, 6H). MS m/z (ESI): 661.4[M+H]⁺.

Example 3.N-(4-((4-amino-2-butyl-1H-imidazo[4,5-c]quinolin-1-yl)oxy)butyl)-1-hexadecylpiperidine-4-carboxamide(3)

Step 1: To a solution of NaH (510 mg, 12.74 mmol) in dry DMF (10 mL) wasadded 3-1 (1.0 g, 6.37 mmol) at −25° C. The reaction mixture was stirredfor 30 min at −25° C. followed by addition of 3-1a (2.91 g, 9.55 mmol).The mixture was allowed to warm to RT and stirred overnight. Afterdiluting with H₂O (100 mL), the mixture was extracted with EA (ethylacetate, 100 mL×3). The combined organics were washed with brine, driedover Na₂SO₄ and concentrated. The residue was purified by silica gelcolumn (PE/EA=100/1-10/1) to give 3-2 (1.5 g, yield: 45.3%) as lightyellow oil, ¹H NMR (400 MHz, CDCl3) δ 4.15-4.10 (m, 2H), 2.89 (d, J=5.5Hz, 2H), 2.32-2.27 (m, 3H), 1.99-1.89 (m, 4H), 1.79-1.78 (m, 2H), 1.48(s, 2H), 1.30-1.23 (m, 29H), 0.88 (t, J=5.5 Hz, 3H).

Step 2: To a solution of 3-2 (500 mg, 6.37 mmol) in EtOH (25 mL) wasadded NaOH/H₂O (4N,15 mL). The reaction solution was stirred at RTovernight. The mixture was concentrated to remove most of ethanol. Theaqueous phase was neutralized with HCl (4N, 15 mL). The crude productstirred with EtOH (25 mL) for 1 h, the solid was collected by filtrationand dried to give 3-3 (350 mg, yield: 75.6%) as white solid. ¹H NMR (400MHz, MeOD) δ 3.45-3.43 (m, 2H), 3.04-2.97 (m, 4H), 2.38 (s, 1H),2.10-2.07 (m, 2H), 1.92 (s, 2H), 1.87 (s, 2H), 1.31-1.26 (m, 26H), 0.90(t, J=5.5 Hz, 3H).

Step 3: To a solution of 3-3 (233 mg, 0.612 mmol) in dry DCM (25 mL) wasadd 1-8 (100 mg, 0.306 mmol),1-Ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC, 116 mg, 0.612 mmol)and DMAP (38 mg, 0.306 mmol). The mixture was stirred at RT for 2 h.After diluting with H₂O (100 mL), the mixture was extracted with DCM(100 mL*3). The organic phase was washed with brine, dried with Na₂SO₄and concentrated. The residue was purified by Pre-HPLC to give Compound3 (16.12 mg, yield: 8%) as off-white solid. ¹H NMR (400 MHz, DMSO-d6) δ8.03 (d, J=5.5 Hz, 1H), 7.80 (s, 1H), 7.59 (d, J=7.8 Hz, 1H), 7.47-7.43(m, 1H), 7.29-7.25 (m, 1H), 6.60 (s, 2H), 4.32 (s, 2H), 3.15 (d, J=8.2Hz, 2H), 2.96-2.92 (m, 2H), 2.83 (d, J=7.2, 7.2 Hz, 2H), 2.22-2.18 (m,2H), 2.05 (s, 1H), 1.88-1.78 (m, 6H), 1.66-1.54 (m, 6H), 1.46-1.23 (m,30H), 0.95 (t, J=5.5 Hz, 3H), 0.85 (t, J=5.5 Hz, 3H). MS m/z (ESI):663.5 [M+H]⁺.

¹H NMR (400 MHz, DMSO-d₆) δ 8.02 (s, 1H), 7.80 (s, 1H), 7.75 (q, J=17.0Hz, 7.5 Hz, 2H), 7.35 (d, J=7.5 Hz, 2H), 7.09 (s, 1H), 7.06 (m, 2H),4.17 (m, 2H), 4.02 (t, J=1.0 Hz, 1H), 3.73 (q, 11.0 Hz, 3 Hz, 1H), 3.22(m, 2H), 2.82 (m, 2H), 2.75 (t, J=3.0 Hz, 1H), 2.57 (m, 2H), 2.39 (m,1H), 2.27 (s, 3H). 2.09 (m, 2H), m/z: 478.2 [M+H]⁺.

Example 4.N-(4-((4-amino-2-butyl-1H-imidazo[4,5-c]quinolin-1-yl)oxy)butyl)-1-hexadecylpiperidine-4-carboxamide(4)

Step 1: To a solution of 4-1 (30.0 g, 184 mmol) and 4-1a (70.1 g, 552mmol) in CH₃CN (500 mL) were added TEA (37.2 g, 368 mmol) and KI (3.05g, 18.4 mmol), the mixture was stirred at 70° C. for 24 h. Afterconcentration, the residue was purified by column chromatography(PE/EA=8:1) to afford 4-2 (32 g, yield: 70%) as a white solid. ¹H NMR(400 MHz, CDCl3) δ 7.85-7.82 (M, 2H), 7.79-7.73 (m, 2H), 4.25 (t, J=6.0Hz, 2H), 3.68 (t, J=6.4 Hz, 2H), 2.11-2.03 (m, 2H), 1.99-1.92 (m, 2H).

Step 2: To a solution of 4-2 (60 g, 238 mmol) in EtOH (1500 mL) wasadded hydrazine (16.8 g, in 30 mL water) and the reaction was stirred atRT overnight. The reaction was cooled in the freezer and the resultingsolid was removed by filtration. The solid was washed with ethanol (400mL). The combined filtrate was concentrated under reduced pressure. Theresidue was mixed with diethyl ether (500 mL). Insoluble impurities wereremoved by filtration and 4.0 M HCl in 1,4-dioxane (100 mL) was added tothe filtrate. A precipitate formed immediately. The mixture was stirredat RT for 2 h, the solid was recovered by filtration and dried undervacuum to give 4-3 (18.2 g, yield: 62.3%) as a white solid. ¹H NMR (400MHz, DMSO-d6) δ 11.06 (s, 2H), 4.03 (t, J=6.0 Hz, 2H), 3.67 (t, J=6.4Hz, 2H), 1.80-1.69 (m, 4H).

Step 3: To a solution of 4-4 (20 g, 112 mmol) in pyridine (50 mL) wasadded Pyr.HCl (1.34 g) and 4-4a (41.6 g, 224 mmol) in 60 mL pyridine.The mixture was stirred at RT overnight. After concentration, theresidue was diluted with 10% sodium carbonate solution (100 mL) andstirred for 30 min. The solid was collected and triturated withPE/EA=5:1 (100 mL) to give 4-5 (25 g, yield: 86.2%) as a yellow solid.¹H NMR (400 MHz, DMSO-d6) δ 10.07 (s, 1H), 9.04 (s, 1H), 8.20 (dd,J=8.4, 1.2 Hz, 1H), 8.09 (dd, J=8.4, 0.8 Hz, 1H), 7.86-7.75 (m, 2H),2.54-2.42 (m, 2H), 1.71-1.49 (m, 2H), 1.48-1.35 (m, 2H), 0.94 (t, J=7.2Hz, 3H).

Step 4: A solution of 4-5 (2.5 g, 9.54 mmol) and 4-3 (2.5 g, 15.5 mmol)in isopropanal (12 mL) was stirred at 85° C. for 5 h under microwave.After concentration, the residue was purified by column chromatography(EA) to afford 4-6 (1.75 g, yield: 56%) as a yellow oil. ¹H NMR (400MHz, CDCl₃) δ 9.29 (s, 1H), 9.05 (d, J=7.0 Hz, 1H), 8.50 (d, J=6.8 Hz,1H), 8.15-7.79 (m, 2H), 4.60-4.43 (m, 2H), 3.72 (t, J=5.0 Hz, 2H), 3.10(t, J=7.2 Hz, 2H), 2.32-2.26 (m, 2H), 2.20-2.12 (m, 2H), 2.02-1.97 (m,2H), 1.58-1.52 (m, 2H), 1.04 (t, J=7.2 Hz, 3H).

Step 5: To a solution of 4-6 (11 g, 33.2 mmol) in DCM (400 mL) was added30% H₂O₂ (55 mL) and m-CPBA (20.2 g, 60.6 mmol) at 0° C., the reactionmixture was allowed to stirred at RT for 16 h under argon atmosphere.Water (200 mL) added to the mixture, and extracted with DCM (200 mL*2).The combined organic layer was washed with sodium carbonate solution(400 mL) and brine (400 mL), dried over sodium sulfate, filtered andconcentrated in vacuo to give 4-7 (10 g, crude), which was used in nextstep directly. MS m/z (ESI): 348.1 [M+H]⁺.

Step 6: To a solution of 4-7 (5.0 g, 14.4 mmol) in DCM (100 mL) wasadded aqueous ammonium hydroxide (5 mL) at 0° C., a solution of TsCl(6.84 g, 36.0 mmol) in 40 mL dichloromethane was slowly added withvigorous stirring. The cooling bath was removed and the reaction wasstirred for an additional 16 h. The mixture was diluted with sodiumcarbonate solution (100 mL) and extracted with DCM (200 mL*2). Thecombined organic layer was washed with brine (400 mL*2), dried oversodium sulfate, filtered and concentrated in vacuo. The residue waspurified by column chromatography (EA/MeOH=10:1) to afford 4-8 (3.2 g,yield: 64%) as a yellow oil. ¹H NMR (400 MHz, CDCl₃) δ 8.09 (d, J=8.0Hz, 1H), 7.90 (d, J=8.0 Hz, 1H), 7.62 (d, J=8.4 Hz, 1H), 7.45 (t, J=7.6Hz, 1H), 4.37 (t, J=6.4 Hz, 2H), 3.69 (t, J=6.0 Hz, 2H), 2.98-2.92 (m,2H), 2.14-2.11 (m, 2H), 1.93-1.88 (m, 4H), 1.52-1.47 (m, 2H), 1.01 (t,J=7.2 Hz, 3H). MS m/z (ESI): 347.2 [M+H]⁺.

Step 7: A solution of 4-8 (1.0 g, 2.89 mmol) in 4-8a (2 mL) was stirredat 70° C. for 6 h. LCMS showed 60% product. The mixture was diluted withwater (10 mL) and extracted with EA (50 mL*10). The combined organiclayer was washed with brine (100 mL), dried over sodium sulfate,filtered and concentrated in vacuo to afford 4-9 (500 mg) as a yellowoil which was used in next step directly. MS m/z (ESI): 413.2 [M+H]⁺.

Step 8: To a solution of 4-9 (230 mg, 0.558 mmol) in DCM (10 mL) wereadded stearic acid (332 mg, 1.116 mmol), EDC (212 mg, 1.116 mmol) andDMAP (68 mg, 0.558 mmol), the mixture was stirred at RT overnight. Themixture was diluted with DCM (20 mL), washed with saturated ammoniumchloride (40 mL) and brine (30 mL). The organic layer was dried oversodium sulfate, filtered, and concentrated in vacuo. The residue waspurified by prep-HPLC (FA) to give the desired product (FA salt), whichwas neutralized with sodium carbonate solution (10 mL) and furtherpurified by prep-TLC (DCM/MeOH=10:1) to give the free base 4 (26 mg,yield: 5.6%) as a yellow oil. ¹H NMR (400 MHz, CDCl₃) δ 8.12 (t, J=8.4Hz, 1H), 7.93 (d, J=8.4 Hz, 1H), 7.63 (dd, J=8.4, 7.2 Hz, 1H), 7.50 (t,J=7.6 Hz, 1H), 4.44-4.33 (m, 2H), 3.53-3.44 (m, 3H), 2.99-2.89 (m, 3H),2.73 (s, 3H), 2.51-2.48 (m, 1H), 2.36-2.31 (m, 3H), 2.34 (dd, J=14.2,6.6 Hz, 2H), 2.17-2.11 (m, 2H), 2.04-1.97 (m, 4H), 1.92-1.80 (m, 4H),1.66-1.61 (m, 2H), 1.53-1.47 (m, 2H), 1.38-1.16 (m, 26H), 1.03-0.93 (m,3H), 0.88 (t, J=6.8 Hz, 3H) MS m/z (ESI): 679.5 [M+H]⁺.

Example 5.N1-(4-((4-amino-2-butyl-1H-imidazo[4,5-c]quinolin-1-yl)oxy)butyl)-N3,N3-dimethyl-N1-octadecylpropane-1,3-diamine(5)

A solution of 4-9 (90 mg, 0.218 mmol) and 5-1 (67 mg, 0.262 mmol) in DCM(12 mL) was stirred at RT for 1 h, NaBH(OAc)₃ (138 mg, 0.654 mmol) wasadded to the mixture and stirred for another 3 h. The mixture wasconcentrated in vacuo and the residue was purified by prep-TLC(DCM/MeOH=10:1) to give the title product 5 (54.4 mg, yield: 29.3%) as alight-yellow oil. ¹H NMR (400 MHz, MeOD) δ 8.27 (dd, J=8.0, 0.8 Hz, 1H),7.76 (dd, J=8.4, 0.8 Hz, 1H), 7.72-7.66 (m, 1H), 7.58-7.53 (m, 1H), 4.49(t, J=6.5 Hz, 2H), 3.06 (dd, J=10.3, 4.8 Hz, 2H), 3.03 (d, J=7.4 Hz,2H), 3.00-2.97 (m, 2H), 2.89 (dd, J=9.9, 6.0 Hz, 2H), 2.75 (s, 6H),2.10-2.05 (m, 2H), 1.99-1.91 (m, 6H), 1.71-1.62 (m, 2H), 1.53 (dd,J=15.1, 7.5 Hz, 2H), 1.39-1.37 (m, 4H), 1.33-1.23 (m, 28H), 1.03 (t,J=7.2 Hz, 3H), 0.89 (t, J=6.8 Hz, 3H). MS m/z (ESI): 665.5 [M+H]⁺.

Example 6.N1-(4-((4-amino-2-butyl-1H-imidazo[4,5-c]quinolin-1-yl)oxy)butyl)-N1-(3-(dimethylamino)propyl)-N2-heptadecyloxalamide(6)

Step 1: To a solution of 4-9 (150 mg, 0.364 mmol) in dry DCM (15 mL) wasadded 6-1 (53.3 mg, 0.437 mmol) in dry DCM (2 mL) dropwise at 0° C.,DIEA (141 mg, 1.092 mmol) was added dropwise. The mixture was stirred atRT for 16 h. The mixture was diluted with H₂O (10 mL) and extract withDCM (20 mL*3). The combined organic phase was washed with brine, driedwith Na₂SO₄ and concentrated. The residue was purified by prep-TLC(DCM/MeOH=6:1) to give the desired product 6-2 (80 mg, yield: 44.2%) asa yellow oil. ¹H NMR (400 MHz, CDCl₃) δ 8.08 (d, J=7.6 Hz, 1H),7.92-7.87 (m, 1H), 7.60 (t, J=7.6 Hz, 1H), 7.47 (t, J=7.6 Hz, 1H), 4.36(t, J=6.0 Hz, 2H), 3.89 (d, J=5.2 Hz, 2H), 3.55 (t, J=6.8 Hz, 2H), 3.44(dd, J=13.8, 6.5 Hz, 2H), 3.00-2.93 (m, 2H), 2.78-2.69 (m, 2H), 2.57 (s,3H), 2.52-2.48 (m, 2H), 2.39 (s, 6H), 2.01 (d, J=8.8 Hz, 2H), 1.91 (dd,J=8.0, 2.8 Hz, 2H), 1.57-1.51 (m, 2H), 1.01 (t, J=7.2 Hz, 3H). MS m/z(ESI): 499.2 [M+H]⁺.

Step 2; To a solution of 6-2 (60 mg, 0.12 mmol) in MeOH/H₂O=4:1 (5 mL)was added NaOH (24 mg, 0.60 mmol). The reaction solution was stirred atRT for 30 min. The mixture was concentrated in vacuo, the residue wasdiluted with water and adjusted to pH=5-6 with HCl. The aqueous wasextracted with DCM/MeOH=10:1(30 mL×2), dried and concentrated in vacuoto give 6-3 (50 mg, crude) as white solid, which was used in next stepdirectly. MS m/z (ESI): 485.6 [M+H]⁺.

Step 3; To a solution of 6-3 (50 mg, 0.103 mmol) in DCM/DMF=4:1 (5 mL)were added 6-3a (52.9 mg, 0.206 mmol), EDCI (39.1 mg, 0.206 mmol) andHOBt (27.8 mg, 0.206 mmol). The mixture was stirred at room temperatureovernight. The mixture was concentrated in vacuo, the residue waspurified by prep-HPLC (HCl) to give the compound 6 (10.03 mg, yield:13.5%, HCl salt) as a yellow solid. ¹H NMR (400 MHz, CDCl₃) δ 14.84 (s,1H), 12.42 (s, 1H), 9.01 (s, 1H), 8.13 (d, J=1.6 Hz, 1H), 7.93 (s, 1H),7.63 (s, 1H), 7.52 (d, J=8.0 Hz, 1H), 6.89 (s, 1H), 4.50-4.39 (m, 2H),4.02-3.84 (m, 2H), 3.67-3.51 (m, 2H), 3.30-3.10 (m, 4H), 3.04-2.94 (m,2H), 2.88-2.86 (m, 4H), 2.39-2.29 (m, 2H), 2.09-1.98 (m, 4H), 1.91-1.89(m, 2H), 1.56-1.51 (m, 4H), 1.30-1.25 (m, 30H), 1.01 (t, J=6.0 Hz, 3H),0.88 (t, J=6.8 Hz, 3H). MS m/z (ESI): 722.6 [M+H]⁺.

Example 7.3-((4-((4-amino-2-butyl-1H-imidazo[4,5-c]quinolin-1-yl)oxy)butyl)(3-(dimethylamino)propyl)amino)-4-(heptadecylamino)cyclobut-3-ene-1,2-dione(7)

To a solution of 4-9 (230 mg, 0.558 mmol) and 7-1 (400 mg, 0.837 mmol)in MeOH (10 mL) was added DIEA (144 mg, 1.116 mmol). The mixture wasstirred at RT for 16 h. The mixture was concentrated in vacuo, theresidue was purified by prep-TLC (DCM/MeOH=10:1) to give the desiredproduct 7 (21.03 mg, yield: 4.9%) as a light-yellow oil. ¹H NMR (400MHz, CDCl₃) δ 8.61 (s, 1H), 8.03 (d, J=8.0 Hz, 1H), 7.80 (d, J=8.0 Hz,1H), 7.50 (t, J=7.6 Hz, 1H), 7.41 (t, J=7.6 Hz, 1H), 4.37 (t, J=6.4 Hz,2H), 3.82 (d, J=6.4 Hz, 2H), 3.72-3.65 (m, 2H), 3.60-3.47 (m, 2H), 2.91(t, J=7.6 Hz, 2H), 2.75-2.65 (m, 2H), 2.44 (s, 6H), 2.05-2.01 (m, 2H),1.93-1.91 (m, 2H), 1.87-1.81 (m, 2H), 1.65-1.58 (m, 2H), 1.45 (dd,J=15.0, 7.5 Hz, 2H), 1.27-1.22 (m, 30H), 0.96 (t, J=7.2 Hz, 3H), 0.84(d, J=7.0 Hz, 3H). MS m/z (ESI): 746.5 [M+H]⁺.

Example 8.2-butyl-1-(4-(4-heptadecyl-1H-1,2,3-triazol-1-yl)butoxy)-1H-imidazo[4,5-c]quinolin-4-amine(8)

Step 1: To a solution of 8-1 (450 mg, 1.411 mmol) in dry DMF (1 mL) wasadded 8-1a (1 M). The reaction mixture reacted at 75 degrees for 3hours. The reaction solution was diluted with H₂O (50 mL) under icewater bath, then extracted with PE/EA=1/1(50 mL×3). The combinedorganics were washed with saturated salt water, dried with Na₂SO₄ andconcentrated. The residue was purified by silica gel column (petroleumether) to give 8-2 (300 mg, yield: 80%) as a white solid. ¹H NMR (400MHz, CDCl₃) δ 2.20-2.16 (m, 2H), 1.93 (t, J=4.0 Hz, 1H), 1.54-1.49 (m,2H), 1.40-1.26 (m, 28H), 0.88 (t, J=8.0 Hz, 3H).

Step 2: To a solution of 4-8 (450 mg, 1.3 mmol) in DMF (10 mL) was addedNaN₃ (169 mg, 2.6 mmol), the mixture was stirred at 80° C. for 16 h. Themixture was diluted with water (100 mL) and extracted with EA (50 mL*3).The combined organic layer was washed with brine (100 mL), dried oversodium sulfate, filtered and concentrated in vacuo. The residue waspurified by column chromatography (PE/EA=1:1) to afford 8-3 (450 mg) asa yellow oil. ¹H NMR (400 MHz, CDCl₃) δ 8.00 (d, J=8.0 Hz, 1H), 7.81 (d,J=8.4 Hz, 1H), 7.51 (t, J=7.6 Hz, 1H), 7.34 (t, J=7.6 Hz, 1H), 4.90 (s,2H), 4.27 (t, J=6.4 Hz, 2H), 3.41 (t, J=6.4 Hz, 2H), 2.93-2.79 (m, 2H),2.08-1.93 (m, 2H), 1.93-1.63 (m, 4H), 1.47-1.38 (m, 2H), 0.94 (t, J=7.2Hz, 3H). MS m/z (ESI): 354.2 [M+H]⁺.

Step 3: To a solution of 8-3 (200 mg, 0.567 mmol) in THF/H₂O=1:1 (20 mL)were added CuSO₄ (18 mg, 0.113 mmol) and Sodium L-Ascorbate (45 mg,0.227 mmol), the mixture was stirred at RT for 1 h. The mixture wasdiluted with water (20 mL) and extracted with EA (30 mL*2). The combinedorganic layer was washed with brine (80 mL), dried over sodium sulfate,filtered and concentrated in vacuo. The residue was purified byprep-HPLC (HCl in water/MeCN) to give the desired product (HCl salt),which was stirred in sat. sodium carbonate overnight to give the freeproduct 3 (103.44 mg, yield: 29.4%) as a white solid. ¹H NMR (400 MHz,CDCl₃) δ 8.04 (d, J=7.6 Hz, 1H), 7.83 (d, J=8.4 Hz, 1H), 7.56 (t, J=7.2Hz, 1H), 7.37 (t, J=7.2 Hz, 1H), 7.30 (s, 1H), 5.88 (s, 2H), 4.48 (t,J=6.4 Hz, 2H), 4.31 (t, J=6.0 Hz, 2H), 2.92 (t, J=7.6 Hz, 2H), 2.73 (t,J=7.6 Hz, 2H), 2.27-2.21 (m, 2H), 2.02-1.98 (m, 2H), 1.92-1.85 (m, 2H),1.70-1.65 (m, 2H), 1.52-1.46 (m, 2H), 1.33-1.25 (m, 28H), 0.99 (t, J=7.2Hz, 3H), 0.88 (t, J=6.4 Hz, 3H). MS m/z (ESI): 618.5 [M+H]⁺.

Example 9.2-butyl-1-(4-(5-heptadecyl-1,3,4-oxadiazol-2-yl)butoxy)-1H-imidazo[4,5-c]quinolin-4-amine(9)

Step 1: To a solution of 4-8 (2.7 g, 7.78 mmol) in DMSO (60 mL) wasadded KCN (1.01 g, 15.6 mmol), the mixture was stirred at 80° C. for 16h. The mixture was diluted with water (100 mL) and extracted with EA(100 mL*3). The combined organic layer was washed with brine (100 mL),dried over sodium sulfate, filtered and concentrated in vacuo. Theresidue was purified by column chromatography (PE/EA=0:1) to afford 9-1(2.6 g, yield: 87%) as a yellow solid. ¹H NMR (400 MHz, CDCl₃) δ 8.04(dd, J=8.0, 1.2 Hz, 1H), 7.83 (d, J=8.0 Hz, 1H), 7.55 (dd, J=11.2, 4.4Hz, 1H), 7.37 (s, 1H), 6.04 (s, 2H), 4.35 (d, J=8.0 Hz, 2H), 2.93 (d,J=8.0 Hz, 2H), 2.56 (d, J=7.2 Hz, 2H), 2.20-2.14 (m, 2H), 2.03 (dd,J=10.0, 5.8 Hz, 2H), 1.89 (d, J=7.6 Hz, 2H), 1.50 (dd, J=15.0, 7.5 Hz,2H), 1.01 (t, J=7.2 Hz, 3H).

Step 2: A solution of 9-1 (800 mg, 2.37 mmol) in con.HCl (2 mL) wasstirred at 100° C. for 4 h. After cooling to rt, the mixture was dilutedwith water (5 mL) and extracted with EA (20 mL*8). The combined organiclayer was dried over sodium sulfate, filtered and concentrated in vacuoto give 9-2 (650 mg, yield: 77%) as a yellow solid. MS m/z (ESI): 357.2[M+H]⁺

Step 3: To a solution of 9-2 (260 mg, 0.73 mmol) in DCM/DMF=4:1 (25 mL)were added stearohydrazide (435 mg, 1.46 mmol), EDCI (277 mg, 1.46 mmol)and HOBt (197 mg, 1.46 mmol), the mixture was stirred at RT overnight.The mixture was concentrated in vacuo, the residue was purified byprep-HPLC (HCl) to give compound 9-3 (120 mg, yield: 25.8%) as a yellowsolid. ¹H NMR (400 MHz, CDCl₃) δ 7.97 (d, J=8.0 Hz, 1H), 7.80 (d, J=8.2Hz, 1H), 7.53 (d, J=7.0 Hz, 1H), 7.31 (s, 1H), 4.23 (t, J=4.4 Hz, 2H),2.94-2.83 (m, 2H), 2.42 (t, J=6.2 Hz, 2H), 2.30-2.22 (m, 2H), 2.07-1.97(m, 4H), 1.87 (dd, J=15.4, 7.5 Hz, 3H), 1.69 (d, J=6.8 Hz, 4H),1.53-1.47 (m, 3H), 1.37-1.21 (m, 36H), 1.00 (t, J=7.2 Hz, 3H), 0.88 (t,J=6.8 Hz, 3H). MS m/z (ESI): 637.5 [M+H]⁺.

Step 4: A solution of 9-3 (120 mg, 0.189 mmol) in POCl₃ (2 mL) wasstirred at 50° C. for 3 h. After cooling to RT, the mixture was pouredinto sodium carbonate solution (30 mL) and extracted with EA (30 mL*2).The combined organic layer was dried over sodium sulfate, filtered andconcentrated in vacuo. The residue was purified by prep-TLC(DCM/MeOH=10:1) to give compound 9 (34.32 mg, yield: 29.3%) as alight-yellow oil. ¹H NMR (400 MHz, CDCl₃) δ 8.07 (d, J=8.0 Hz, 1H), 7.83(d, J=8.4 Hz, 1H), 7.56 (t, J=7.6 Hz, 1H), 7.38 (t, J=7.6 Hz, 1H), 6.07(s, 2H), 4.35 (t, J=5.6 Hz, 2H), 2.97 (dt, J=15.4, 7.3 Hz, 4H), 2.83 (t,J=7.6 Hz, 2H), 2.14 (dd, J=16.1, 2.9 Hz, 4H), 1.89 (dt, J=15.3, 7.6 Hz,2H), 1.79 (dd, J=14.8, 7.5 Hz, 2H), 1.49 (dd, J=15.0, 7.4 Hz, 2H),1.31-1.25 (m, 28H), 1.00 (t, J=7.2 Hz, 3H), 0.88 (t, J=6.8 Hz, 3H). MSm/z (ESI): 619.5 [M+H]⁺.

Example 10.2-butyl-1-(4-(5-heptadecyl-1,2,4-oxadiazol-3-yl)butoxy)-1H-imidazo[4,5-c]quinolin-4-amine(10)

Step 1: To a stirred solution of 9-1 (500 mg, 1.48 mmol) in EtOH (20 mL)under argon atmosphere were added hydroxylamine hydrochloride (512 mg,7.42 mmol) and TEA (749 mg, 7.42 mmol), the mixture was stirred at RTfor 16 h. The reaction was concentrated in vacuo and the residue waspurified by column chromatography (DCM/MeOH=10:1 to 4:1) to give 10-2(70 mg, yield: 12.8%) as a light green solid. ¹H NMR (400 MHz, DMSO-d6)δ 8.08 (d, J=8.0 Hz, 1H), 7.66 (d, J=8.0 Hz, 1H), 7.57-7.52 (m, 1H),7.41-7.37 (m, 1H), 4.38-4.33 (m, 2H), 2.98-2.94 (m, 2H), 2.70-2.64 (m,2H), 2.35-2.29 (m, 2H), 1.87-1.77 (m, 4H), 1.46-1.41 (m, 2H), 0.95 (t,J=7.2 Hz, 3H). MS m/z (ESI): 371.3 [M+H]⁺.

Step 2: To a solution of 10-2 (70 mg, 0.189 mmol) and stearic acid (107mg, 0.378 mmol) in DMF/DCM=1:4 (10 mL) was addedN,N′-dicyclohexylcarbodiimide (DCC, 77.9 mg, 0.378 mmol), the mixturewas stirred at RT for 20 h. The mixture was concentrated in vacuo toremove DCM and the residue was purified by prep-HPLC (FA) to give 10-3(17 mg, yield: 14.2%) as a yellow solid. MS m/z (ESI): 637.5 [M+H]⁺.

Step 3: A solution of 10-3 (17 mg, 0.026 mmol) in DMF (2 mL) was stirredat 120° C. for 4 h. The mixture was purified by prep-HPLC (HCl) to givecompound 10 (2.60 mg, yield: 15.7%) as a light solid. ¹H NMR (400 MHz,CD3OD) δ 8.30 (d, J=8.0 Hz, 1H), 7.77 (d, J=4.0 Hz, 2H), 7.66 (dd,J=8.0, 4.0 Hz, 1H), 4.51-4.47 (m, 2H), 3.08-3.03 (m, 2H), 2.95-2.86 (m,4H), 2.09-2.07 (m, 2H), 2.06-1.98 (m, 2H), 1.97-1.91 (m, 2H), 1.83-1.77(m, 2H), 1.64-1.57 (m, 2H), 1.54-1.50 (m, 2H), 1.30-1.23 (m, 26H), 1.02(t, J=7.2 Hz, 3H), 0.88 (d, J=7.2 Hz, 3H). MS m/z (ESI): 619.9 [M+H]⁺.

Example 11.2-butyl-1-(4-(3-heptadecyl-1,2,4-oxadiazol-5-yl)butoxy)-1H-imidazo[4,5-c]quinolin-4-amine(11)

Step 1: To a solution of NH₂OH—HCl (417 mg, 6.04 mmol) in isopropanol(15 mL) was added NaHCO₃(761 mg, 9.06 mmol), the mixture was stirred atRT for 30 min, then 11-1 (800 mg, 3.02 mmol) was added to the mixtureand stirred at 80° C. overnight. The mixture was filtered to give 11-2(600 mg, yield: 66.7%) as a white solid. ¹H NMR (400 MHz, DMSO-d6) δ8.65 (s, 1H), 5.27 (s, 2H), 1.94-1.90 (m, 2H), 1.44 (d, J=6.4 Hz, 2H),1.23 (s, 28H), 0.85 (t, J=6.8 Hz, 3H).

Step 2: To a solution of 11-2 (146 mg, 0.504 mmol) and 9-10 (150 mg,0.42 mmol) in dioxane/DCM=1:1 (16 mL) was added DCC (173 mg, 0.84 mmol),the mixture was stirred at RT for 2 h. The mixture was concentrated invacuo, the residue was purified by prep-TLC (DCM/MeOH=10:1) to give 13-3(180 mg, yield: 67.4%) as a yellow solid. ¹H NMR (400 MHz, CDCl₃) δ 8.09(d, J=8.0 Hz, 1H), 7.88 (d, J=8.4 Hz, 1H), 7.61-7.57 (m, 1H), 7.44-7.40(m, 1H), 4.34 (t, J=6.0 Hz, 2H), 2.98-2.92 (m, 2H), 2.58 (t, J=6.8 Hz,2H), 2.28-2.22 (m, 2H), 2.09-2.01 (m, 4H), 1.90 (d, J=7.7 Hz, 4H),1.63-1.59 (m, 2H), 1.53-1.48 (m, 2H), 1.37-1.24 (m, 26H), 1.00 (t, J=7.2Hz, 3H), 0.88 (t, J=6.8 Hz, 3H).

Step 3: A solution of 13-3 (180 mg, 0.283 mmol) in DMF (5 mL) wasstirred at 120° C. for 4 h. The mixture was purified by prep-HPLC (HCl)to give compound 11 (63.61 mg, yield: 36%) as a light-yellow solid (HClsalt). ¹H NMR (400 MHz, CDCl₃) δ 15.09 (s, 1H), 9.09 (s, 1H), 8.12 (d,J=8.0 Hz, 1H), 8.00 (d, J=8.0 Hz, 1H), 7.71 (d, J=7.2 Hz, 1H), 7.57 (d,J=7.2 Hz, 1H), 7.00 (s, 1H), 4.43 (d, J=2.4 Hz, 2H), 3.10-2.93 (m, 4H),2.76-2.68 (m, 2H), 2.20-2.08 (m, 4H), 2.04-1.91 (m, 4H), 1.76 (dd,J=14.6, 7.6 Hz, 2H), 1.52 (dt, J=14.3, 7.2 Hz, 2H), 1.39-1.22 (m, 26H),1.02 (t, J=7.3 Hz, 3H), 0.88 (t, J=6.8 Hz, 3H). MS m/z (ESI): 619.5[M+H]⁺.

Example 12.3-(4-(4-amino-2-butyl-1H-imidazo[4,5-c]quinolin-1-yloxy)butylamino)-4-((3-(dimethylamino)propyl)(heptadecyl)amino)cyclobut-3-ene-1,2-dione(12)

Step 1: A solution of 5-1 (0.3 g, 1.18 mmol) and 4-8a (120.47 mg, 1.18mmol) in MeOH (20 mL) was stirred at 30° C. for 3 hours, NaBH₄ (44.61mg, 1.18 mmol) was added to the mixture and stirred at 30° C. foranother 16 hours. LCMS showed product was formed. The mixture wasdiluted with water (20 mL), extracted with EtOAc (40 mL*2). The combinedorganic layer was dried over sodium sulfate, filtered and concentratedin vacuo to give 12-1 (0.3 g, 75% yield) as a light yellow oil, whichwas confirmed by HNMR. ¹H NMR (400 MHz, CDCl3) δ 2.65 (t, J=6.8 Hz, 2H),2.59 (t, J=7.2 Hz, 2H), 2.33-2.29 (m, 2H), 2.22 (s, 6H), 1.70-1.65 (m,2H), 1.50-1.44 (m, 1H), 1.32-1.20 (m, 28H), 0.87 (d, J=6.8 Hz, 3H).

Step 2: A solution of 12-1 (0.3 g, 0.880 mmol) and 12-2 (125.2 mg, 0.880mmol) in MeOH (20 mL) was stirred at 30° C. for 4 hours. TLC(DCM/MeOH=10:1) showed the reaction was completed. The mixture wasconcentrated in vacuo, the residue was purified by column chromatography(DCM/MeOH=10:1) to give compound 12-3 (0.28 g, 71% yield) as a lightyellow oil. MS m/z (ESI) 451.2 [M+H]⁺.

Step 3: To a solution of 12-3(42.0 mg, 0.093 mmol) and compound A (30.5mg, 0.093 mmol) in MeOH (4 mL) was added DIEA (24.1 mg, 0.186 mmol,32.46 uL), the mixture was stirred at room temperature for 16 hours.LCMS showed the reaction was completed. The mixture was concentrated invacuo, the residue was purified by prep-HPLC (0.05% HCl) to giveCompound 12 as HCl salt (37 mg, 53% yield) as a white solid. ¹H NMR (400MHz, MeOD) δ 8.19 (d, J=7.6 Hz, 1H), 7.76 (d, J=8.0 Hz, 1H), 7.68 (t,J=7.2 Hz, 1H), 7.58 (t, J=7.2 Hz, 1H), 4.50 (br.s, 2H), 3.86-3.55 (m,6H), 3.29-3.22 (m, 2H), 3.04 (t, J=7.2 Hz, 2H), 2.94 (s, 6H), 2.14-2.11(m, 4H), 2.01-1.88 (m, 4H), 1.67 (br.s, 2H), 1.57-1.48 (m, 2H),1.34-1.19 (m, 28H), 1.02 (t, J=7.2 Hz, 3H), 0.87 (t, J=6.8 Hz, 3H). MSm/z (ESI) 746.5 [M+H]⁺.

Example 13. TLR7/8 agonists induce IFN-gamma and TNF-alpha release inhuman PBMC

The system is used to assess the cytokines release. Activity is based onthe measurement of interferon-gamma (IFN-γ) and tumor necrosisfactor-alpha (TNF-α) secreted into culture media.

Isolation of PBMCs

Fresh human blood was diluted with the same volume of PBS, 15 mLLymphoprep was added into a Sepmate tube, then 30 mL diluted blood wasadded on the top gently without disturbing the interface.

The Sepmate tube was centrifuged for 25 min at 1000×g at RT with brakeoff.

The buffy coat containing peripheral blood mononuclear cells (PBMCs) wascollected from Sepmate tube and transferred into a new tube, and thecells were washed with 40 mL PBS twice and centrifuged at 350×g for 5min.

PBMCs were resuspended in complete culture medium at a density of2E6/mL.

Compound Preparation

The compounds are solubilized in dimethyl sulfoxide (DMSO) and dilutedinto indicated concentration with complete culture medium.

The compounds are tested at final concentrations 100 μM, 33.3 μM, 11.1μM, 3.7 μM, 1.23 μM, 0.41 μM, 0.137 μM, 0.0457 μM and 0. 0152 μM.

Incubation

2*10^5 PBMCs (in 100 μL) were added to each well of 96-well flat bottomplate.

2× final concentration of 3-fold serial diluted compounds (in 100 μL)were added to indicated wells and final volume was 200 μL.

The plate was covered with sterile lids, mixed gently and then incubatedfor 24 h at 37° C./5% CO₂ incubator.

Separation Supernatant

Following incubation, the plates was centrifuged for 5 min. at 400×g.The cell-free culture Supernatant was removed into a non-sterilepolypropylene plate. Samples are maintained at −80° C. until analysis.The samples were analyzed for TNF-α and IFN-γ by ELISA according to thedirection.

TNF-α and IFN-α were analyzed by ELISA. IFN-α concentration wasdetermined by ELISA using a Human IFN-α ELISA Kit from R&D Systems(Catalog #41100-2) and read on VICTOR Nivo™ from PerkinElmer. Resultswere expressed in pg/mL. TNF-α concentration was determined by ELISAusing a Human TNF-alpha ELISA MAX™ Deluxe from BioLegend (Catalog#430205) and read on VICTOR Nivo™ from PerkinElmer. Results wereexpressed in pg/mL.

The data was analyzed to determine the minimum effective concentration(MEC) for each compound at which induction of a particular cytokine wasobserved in the assay. Specifically, the MEC of each compound(micromolar) was determined as the lowest concentration of the compoundthat induced a measured cytokine response at a level (pictograms/mL)that was at least 2× greater than that observed with the negativecontrol wells. The results are presented in Table 2.

TABLE 2 MEC to induce cytokine (micromolar) Compound IFN-alpha TNF-alphaExample 1 >33.3 11.1 Example 2 0.0152 0.0457 Example 3 0.137 0.137Example 4 33.3 33.3 Example 5 1.23 11.1 Example 6 >100 >100 Example 70.0152 0.41 Example 8 0.137 0.41 Example 8 3.7 33.3 Example 10 11.1 3.7Example 11 11.1 33.3 Example 12 0.0152 0.41Exemplary Pharmaceutical Preparations

(A) Injection vials: A solution of 100 g of an active ingredientaccording to the invention and 5 g of disodium hydrogen phosphate in 3 Lof distilled water is adjusted to pH 6.5 using 2 N hydrochloric acid,sterile filtered, transferred into injection vials, is lyophilized understerile conditions and is sealed under sterile conditions. Eachinjection vial contains 5 mg of active ingredient.

(B) Suppositories: A mixture of 20 g of an active ingredient accordingto the invention is melted with 100 g of soy lecithin and 1400 g ofcocoa butter, is poured into moulds and is allowed to cool. Eachsuppository contains 20 mg of active ingredient.

(C) Solution: A solution is prepared from 1 g of an active ingredientaccording to the invention, 9.38 g of NaH₂PO₄.2 H₂O, 28.48 g ofNa₂HPO₄.12 H₂O and 0.1 g of benzalkonium chloride in 940 ml ofbidistilled water. The pH is adjusted to 6.8, and the solution is madeup to 11 and sterilized by irradiation. This solution could be used inthe form of eye drops.

(D) Ointment: 500 mg of an active ingredient according to the inventionis mixed with 99.5 g of Vaseline under aseptic conditions.

(E) Tablets: A mixture of 1 kg of an active ingredient according to theinvention, 4 kg of lactose, 1.2 kg of potato starch, 0.2 kg of talc and0.1 kg of magnesium stearate is pressed to give tablets in aconventional manner in such a way that each tablet contains 10 mg ofactive ingredient.

(F) Coated tablets: Tablets are pressed analogously to Example E andsubsequently are coated in a conventional manner with a coating ofsucrose, potato starch, talc, tragacanth and dye.

(G) Capsules: 2 kg of an active ingredient according to the inventionare introduced into hard gelatin capsules in a conventional manner insuch a way that each capsule contains 20 mg of the active ingredient.

(H) Ampoules: A solution of 1 kg of an active ingredient according tothe invention in 60 l of bidistilled water is sterile filtered,transferred into ampoules, is lyophilized under sterile conditions andis sealed under sterile conditions. Each ampoule contains 10 mg ofactive ingredient.

(I) Inhalation spray: 14 g of an active ingredient according to theinvention are dissolved in 101 of isotonic NaCl solution, and thesolution is transferred into commercially available spray containerswith a pump mechanism. The solution could be sprayed into the mouth ornose. One spray shot (about 0.1 ml) corresponds to a dose of about 0.14mg.

Applicant's disclosure is described herein in preferred embodiments withreference to the Figures, in which like numbers represent the same orsimilar elements. Reference throughout this specification to “oneembodiment,” “an embodiment,” or similar language means that aparticular feature, structure, or characteristic described in connectionwith the embodiment is included in at least one embodiment of thepresent invention. Thus, appearances of the phrases “in one embodiment,”“in an embodiment,” and similar language throughout this specificationmay, but do not necessarily, all refer to the same embodiment.

The described features, structures, or characteristics of Applicant'sdisclosure may be combined in any suitable manner in one or moreembodiments. In the description, herein, numerous specific details arerecited to provide a thorough understanding of embodiments of theinvention. One skilled in the relevant art will recognize, however, thatApplicant's composition and/or method may be practiced without one ormore of the specific details, or with other methods, components,materials, and so forth. In other instances, well-known structures,materials, or operations are not shown or described in detail to avoidobscuring aspects of the disclosure.

In this specification and the appended claims, the singular forms “a,”“an,” and “the” include plural reference, unless the context clearlydictates otherwise.

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art. Although any methods and materials similar or equivalent tothose described herein can also be used in the practice or testing ofthe present disclosure, the preferred methods and materials are nowdescribed. Methods recited herein may be carried out in any order thatis logically possible, in addition to a particular order disclosed.

INCORPORATION BY REFERENCE

References and citations to other documents, such as patents, patentapplications, patent publications, journals, books, papers, webcontents, have been made in this disclosure. All such documents arehereby incorporated herein by reference in their entirety for allpurposes. Any material, or portion thereof, that is said to beincorporated by reference herein, but which conflicts with existingdefinitions, statements, or other disclosure material explicitly setforth herein is only incorporated to the extent that no conflict arisesbetween that incorporated material and the present disclosure material.In the event of a conflict, the conflict is to be resolved in favor ofthe present disclosure as the preferred disclosure.

EQUIVALENTS

The representative examples are intended to help illustrate theinvention, and are not intended to, nor should they be construed to,limit the scope of the invention. Indeed, various modifications of theinvention and many further embodiments thereof, in addition to thoseshown and described herein, will become apparent to those skilled in theart from the full contents of this document, including the examples andthe references to the scientific and patent literature included herein.The examples contain important additional information, exemplificationand guidance that can be adapted to the practice of this invention inits various embodiments and equivalents thereof.

What is claimed is:
 1. A compound having the structural formula (I):

wherein, R¹ is a C₁-C₈ alkyl group; R² is (CH₂)_(m), wherein m is aninteger selected from 1 to 8; L is a linking moiety comprising a groupselected from:

and R³ is a C₁-C₃₂ alkyl group; or a pharmaceutically acceptable form oran isotope derivative thereof.
 2. The compound of claim 1, wherein R¹ isa C₃-C₆ alkyl group, m is an integer selected from 3 to 8, and R³ is aC₁₂-C₃₂ alkyl group.
 3. The compound of claim 2, wherein R¹ is a C₄alkyl group, having the structural formula:


4. The compound of claim 3, wherein m is 4, having the structuralformula:


5. The compound of claim 1, wherein L comprises a group selected from:


6. The compound of claim 1, having the structural formula of:


7. The compound of claim 1, having the structural formula of:


8. The compound of claim 1, having the structural formula of:


9. The compound of claim 1, having the structural formula of:


10. The compound of claim 1, having the structural formula of:


11. The compound of claim 1, having the structural formula of:


12. The compound of claim 1, having the structural formula of:


13. The compound of claim 1, having the structural formula of:


14. The compound of claim 1, having the structural formula of:


15. The compound of claim 1, having the structural formula of:


16. The compound of claim 1, having the structural formula of:


17. The compound of claim 1, having the structural formula of:


18. A pharmaceutical composition comprising a compound of claim 1.